[[StargateSG1/AToF Tropes A-F]] | [[StargateSG1/GToL Tropes G-L]] | [[StargateSG1/MToR Tropes M-R]] | '''Tropes S-Z''' | [[YMMV/StargateSG1 YMMV]] | [[ShoutOut/StargateSG1 Shout-Outs]]
!!!''Series/StargateSG1'' provides examples of the following tropes:


* SamusIsAGirl:
** The pilot has a (extremely brief) moment of confusion with regards to Carter. When General Hammond mentions that their foremost expert on the Stargate, Sam Carter, will be arriving soon, O'Neill asks where he is transferring from, only for Carter to walk in at that point and say that ''she'' is transferring from the Pentagon.
** Vala Mal Doran is introduced in "Prometheus Unbound" in the armor of a Kull Warrior with an artificially-deepened voice. She has already taken the ''Prometheus'' and flirted with Daniel Jackson before the helmet is removed to reveal that she is a woman. Daniel finds it extremely disturbing even after the reveal.
* SanityHasAdvantages: The Goa'uld as a whole. Sure, they have an enormous technological advantage thanks to their genetic memory, but said memories as well as abuse of the sarcophagi mean they are all megalomaniacal cliché villains. Furthermore, most of them believe in their own propaganda about being gods, and act with the expected supreme arrogance. The System Lords spend most of their time and resources fighting each other rather than dealing with their common enemies, which both Tok'ra and Tau'ri gladly take advantage of. They also [[WeHaveReserves waste their soldiers]] by [[BadBoss slaying them for the slightest failure]] or [[HonorBeforeReason insisting they always fight to the death]], even against disastrous odds, rather than withdraw to win another day. The Goa'uld were the dominant species of the Milky Way until season 8, but they would have been much more powerful if only they had ''co-operated'' from the start, rather than being forced to by Anubis or the Replicators. Notably, the few System Lords that don't buy fully the godly nonsense (like Ba'al, or Yu before he went senile) are portrayed as much smarter and dangerous than their brethren.
* SavingTheWorldWithArt: In "Learning Curve", the team discovers a planet where certain children soak up knowledge and then have it all removed from their minds in order to distribute to the entire population, after which they are reduced to an infant-like state. Since the society has lost the ability to teach through traditional means, these children are put into care homes for the remainder of their lives. Appalled by this practice, but unable to do anything about it, O'Neill makes one girl spend her last day "acting like a kid" by playing games with other children and learning how to paint before giving up her knowledge. Next time SG-1 visits, it is completely transformed with children playing games and adults drawing pictures. The previously neglected children are now being cared for and reeducated, allowing them to have a new life where previously they had none.
* SawStarWarsTwentySevenTimes: Teal'c and O'Neill drop by Carter's place with pizza and ''Franchise/StarWars'', which O'Neill assumes must be be an okay movie because T's watched it nine times. Carter, however, thinks ''O'Neill'' is the weird one.
-->'''Carter:''' You've ''never'' watched ''Star Wars''?\\
'''O'Neill:''' Oh, come on Carter. [[HypocriticalHumor You know me and sci-fi]].
* ScaryDogmaticAliens:
** The Goa'uld and the Ori.
** After being indoctrinated by the Goa'uld over the millennia, the Jaffa look like this, especially the Free Jaffa Nation. Teal'c frequently shows irritation that they're stuck in the "old ways" even after they gained their freedom in Season 8.
** The Bedrosians from "New Ground". Unlike the Optricans, their rivals from another continent, they refuse to believe their people were once slaves brought through a gateway by an alien being, posing as a god. It just ''had'' to be this world the SGC happened to cold-dial, just as one of their scientists uncovered the Stargate....
* SciFiNameBuzzwords: When Vala [[OffToSeeTheWIzard pitches a story idea based on]] ''Film/TheWizardOfOz'', she tries to disguise it by renaming the primary events characters with Stargate-themed titles. The house caught in a tornado becomes a cargo ship that crashes on a planet, the Wicked Witch of the East is the local ruling Goa'uld, Glinda the Good Witch is "a lovely, fair-haired Tok'ra" and Oz is a wise Ascended being. Martin Lloyd sees right through the whole thing.
* SciFiWritersHaveNoSenseOfScale:
** For the most part averted. Traveling between different stellar systems, even at faster than light speeds, takes months or years (the fastest Goa'uld ship encountered can travel at 32,000 times the speed of light, which would take three years to cross the diameter of the Milky Way Galaxy), which is why the Stargate Network is still vital to the Goa'uld economy and military complex. The concept of conquering a planet requires millions of soldiers and defending a planet, even with technologically-advanced weaponry, requires numerous weapons placed all around the planet, not just at vital areas. Multiple characters point out the flawed thinking of other people when they fall into the traditional pitfalls of discounting the sheer size of the universe.
** The writers still messed up when describing an alien planet as being "several billion miles" away from Earth. The closest star to Earth (other than the Sun, obviously) is Alpha Centauri, which is 25 ''trillion'' miles away. The planet they're describing is far more likely to be hundreds of trillions or even quadrillions of miles distant. It should be noted that the quote comes from Teal'c, who seems to be wildly inaccurate about scale, likely due to Goa'uld propaganda. The same guy who thought a Hatak could travel "ten times the speed of light".
* ScrewTheRulesIHaveConnections: After they have saved the world numerous times SG-1 is able to place direct calls to the President of the United States when they need a favor.
* ScrewTheRulesImDoingWhatsRight: This trope is used quite a bit.
** In the pilot episode, [[SpellMyNameWithAnS O'Neill(with two 'L's)]] admits, in his roundabout way, that his report on the [[Film/{{Stargate}} first trip]] was not ''completely'' accurate because a) genocide against the Abydonian slaves would not be right and b) technically, they ''did'' nuke Ra, who was the actual threat.
** In the first season episode "Enigma", Daniel Jackson goes against orders to help the Tollan get to their stargateless new world. Not being a member of the formal command structure and a vital asset, he gets away with it.
** In the first season finale "Within the Serpent's Grasp", the whole of SG-1 disobeys orders to launch a first strike against Apophis and his assault upon the planet after the [[ObstructiveBureaucrat Obstructive]] and CorruptBureaucrat Senator Robert Kinsey shuts down Stargate Command.
** In the Ori arc, three ascended Ancients are shown to do this to help humanity. Merlin de-ascended to develop a weapon capable of killing the Ori, Orlin did the same to help develop a cure to the Ori plague, and Morgan Le Fay just flat-out broke the rules by intervening while still ascended (which she could get away with because she was no longer in Ancient territory).
* ScrewYouElves:
** Done most often by O'Neill, to the Asgard, Tollan, and the Tok'ra. The Asgard must find it funny, and actually listen to him. The Tollan were eventually [[spoiler:wiped out]], after demonstrating the shallowness of their principles.
** Daniel tries to do it to the Ancients, but they ignore him.
* SealedEvilInACan:
** The Goa'uld Osiris is literally sealed inside a canopic jar.
** Linea, the Destroyer of Worlds, is trapped in an inescapable prison until SG-1 [[NiceJobBreakingItHero breaks her out]].
** The Goa'uld Maruk was spot-welded into his own sarcophagus (along with hungry animal).
** The Goa'uld Hathor was sealed in her sarcophagus by Ra. This was the only nice thing Ra ever did for humanity.
* SealedEvilInADuel:
** [[spoiler:Oma vs. Anubis.]]
** [[spoiler:Morgan Le Fay vs. Adria.]]
* SeasonFinale
* SecretGovernmentWarehouse: In "Point of View", the alternate Carter and Kawalsky arrive in our reality in one. It looks like it could've been filmed in the props department.
* SeinfeldianConversation: When Mitchell, Daniel and SG-22 have managed to capture a Prior, Mitchell spends a lengthy period trying to get the Prior to discuss the recipes of the Ori home galaxy. He, in turn, explains how to make a delicious omelette, and is disappointed when the Prior will not even give a pie crust.
* SelfDeprecation:
** Season eight's "Citizen Joe" features a man who is unwittingly receiving visions of events that occur throughout the series and tries to publish short stories based on them. The writers took this opportunity to poke fun at some of their more disappointing episodes and plotlines, along with persistent issues among fans of the show.
** Both the 100[-[[superscript:th]]-] and 200[-[[superscript:th]]-] episodes celebrate by spending the episodes poking fun at their own show general Sci-Fi clichés.
** Sam's [[EarlyInstallmentWeirdness "Reproductive Organ" speech]] from the pilot returns only to be mocked in "Moebius, Part 1".
* SelfHealingPhlebotinum: Human-form Replicators can regenerate from damage dealt by virtually any weapon except the [[WeaponOfXSlaying anti-Replicator gun]]. Regular Replicators are also sometimes seen reforming after being blown apart, though there's apparently a critical mass of intact blocks that have to be within a certain distance of each other for this to work.
* SelfInsertFic: "Wormhole X-Treme!" reveals that when Martin originally wrote his treatment for the ShowWithinAShow, it had a fifth character based on himself, which he describes as a handsome alien marooned on Earth when his crew betrayed him. The executives took that part out.
* SelfParody: The self-referential episodes "Wormhole X-Treme!" and "200" revolve around the making of a ShowWithinAShow based on the exploits of SG-1, with many jokes and insults aimed at sci-fi clichés and past stories of the SGC.
* SemperFi: SG-3 is a dedicated combat support group composed of US Marines. It was originally commanded by Colonel Makepeace, former TropeNamer of HeroOfAnotherStory, and then led by Colonel Reynolds in the later seasons. SG-5 and SG-18 are also drawn from the Marines.
* SendInTheClones: Ba'al's clones (to great comedic effect) and, to a much lesser extent, the Asgard.
* ShaggyFrogStory: Combined with BrickJoke when O'Neill tries to tell the story about the dog and the dancing monkeys.
-->'''Col. O'Neill:''' Haven't you guys heard the story about the dog and the dancing monkeys? It's about getting along and... dancing.
* ShameIfSomethingHappened:
** In "Prodigy", when a group of scientists disparage O'Neill's experience and right to be in command, Teal'c walks up and "strongly advises" that the scientists listen to O'Neill. Afterwards, O'Neill calls Teal'c "[[LampshadeHanging Rocco]]".
** Arkad, a Jaffa hoping to lead others to follow the Ori, attempts to bully Earth into not opposing his plans by informing them of a plan to attack the planet that he can help them thwart. SG-1 and General Landry are well aware of exactly what he is doing, and do not even let him finish his speech before ridiculing his actions and likening him to a criminal thug.
* ShellShockedVeteran: Vernon in "Sight Unseen". Due to his experiences during the Gulf War, he comes to believe that the creatures being seen in Colorado Springs are due to government experimentation, recognizing that the cover story about a toxic spill is ''clearly'' bogus. O'Neill eventually cops to it and admits Vernon is RightForTheWrongReasons.
* ShipTease: O'Neill and Carter being the biggest case. You know you are being teased when every non-military alternate version of Carter is married to the O'Neill of her reality.
* ShirtlessScene: Frequently.
* ShootTheShaggyDog: "Ethon". SG-1 successfully mediates a truce between the two nations, [[spoiler:only for them to destroy each other immediately after they leave]].
* ShotToTheHeart: Happens in the episode "Avatar", in which Teal'c gets trapped in a virtual reality training program that shocks him every time he dies to increase the realism. The doctor monitoring him has to administer an adrenaline shot when his heart stops after dying for the umpteenth time.
* ShowWithinAShow: ''Wormhole X-Treme!'', used twice to great comedic effect, including the celebrated 200[-[[superscript:th]]-] episode. Its original run was cancelled after airing three episodes, but it sold so well on DVD that the studio decided to give it a movie adaptation. The production of the movie was then fraught with issues and the studio decided to cancel production, but decides to relaunch the series again and it airs for ten years, with the movie greenlit (again) after the two-hundredth episode of the series.
* SideEffectsInclude:
** Invoked as GallowsHumour, when they think the Gate might have caused Daniel to have developed full-blown schizophrenia:
--->'''Jack:''' Why can't we just put a little sign on the end of the ramp, "''Warning: Gate travel might be hazardous to your health!''" I could live with that?!
** Also when testing the anti-prior device for the first time:
--->'''Daniel:''' That warm, fuzzy feeling you're experiencing may be the effects of a device that is inhibiting your ability to concentrate and focus your powers.\\
'''Mitchell:''' Symptoms may include dizziness, irritability...\\
'''Daniel:''' Nausea.\\
'''Mitchell:''' Mild nausea, and a condition known as hot dog fingers.
* SigilSpam:
** You won't find the Ori symbol just on the Book of Origins' cover. In their galaxy, it is ''everywhere'' -- on the Prior's clothes, the crusaders' weapons, the light fixtures, the fire pits they execute nonbelievers in, the power sources in their ships... even ''the ships themselves'' follow the pattern.
** To a lesser degree, the System Lords invoke this by adorning all their Jaffa with their own respective sigil.
* SignatureItemClue: In one episode, SG-1 goes to a planet they've never been to before and find a pack of Russian cigarettes. When they get back they have a little chat with the Russians about what they were doing there and what they found.
* SiliconBasedLife: The Gadmeer ("Scorched Earth") are sulfur-based.
* SincerityMode: When discussing the Goa'uld Nerus, who has contacted the SGC in the hopes of working together against the Ori, General Landry says that he had nice things to say about SG-1. The scene then cuts to Daniel Jackson reading Nerus' communication and he remarks with surprise that Nerus really did have some very nice things to say about SG-1.
* SingleBiomePlanet: {{Deconstructed}}, as the characters often decree the nature an entire planet based only on a brief exploration of the area surrounding the gate. One member concluded that she was on an "ice planet" when she found herself in Antarctica by mistake, and many characters point out that a day of exploration does not come close to discovering what might be just out of visual range.
* SinisterMinister:
** The Canon on the medieval planet in "Demons" made use of ''creative'' interpretations of Literature/TheBible, the fear engendered by the Goa'uld System Lord Sokar's raids for hosts, and a [[AppliedPhlebotinum lightning-summoning ring]] in order to maintain control over his village. When SG-1 arrived, he accused Teal'c of consorting with demons.
** All the Priors of the Ori are downright scary.
** Averted with Jaffa Priests and Priestesses, who despite being forced to worship the Goa'uld for most of the series, tend to be some of the most unambiguously heroic and level-headed of all Jaffa.
* SkeletonGovernment: The Goa'uld.
* SlidingScaleOfContinuity: The show has multi-season {{Myth Arc}}s and smaller storylines but the individual episodes are pretty self-contained, and the show usually has a PreviouslyOn segment in continuity-heavy episodes.
* SlidingScaleOfIdealismVsCynicism: Contrasts Daniel Jackson, who cares about making friends and allies, to the NID, who care about getting technology to defend Earth at any cost, and Jack O'Neill, who is somewhere in the middle, mostly on the side of pragmatism. An example of the show running on different points of the scale is "Scorched Earth", where Daniel finds a way to save both civilizations vying for control of the planet's ecosystem despite Jack's plan to blow one of them up with a naqadah bomb, and "Entity", where Daniel and Sam's idealism leads to the latter being possessed by a vengeful (our probes accidentally caused damage to them) computer entity, even then Daniel insists Sam trying to make contact with the creature was not the wrong move. The entity only releases its hold on her when Jack threatens to send more probes. Jack basically has to tell Daniel to shut up, and let him do it his way.
* SmartPeoplePlayChess: Samantha Carter plays chess with Cassandra every Saturday. Cassandra mentions O'Neill, and states that he's not as dumb as he pretends to be. The example she gives of his ObfuscatingStupidity is that he insists on calling the knight pieces "horses".
* SmellsSexy: Hathor's breath in the episode "Hathor".
* SoBeautifulItsACurse: At least one minor character uses this trope almost verbatim, with the justification that [[PuppeteerParasite Goa'uld]] always want attractive hosts, so being too pretty is more than just a social problem. Since said character was captured as a girl and trapped as a Goa'uld host for god-only-knows how long until her symbiote was killed, it really was AFateWorseThanDeath.
* SocietyOnEdgeEpisode: This show has multiple episodes involving this. One example is season eight's "Full Alert," where the Goa'uld attempt to trigger WorldWarIII between Russia and the United States.
* SoftSpokenSadist: The Goa'uld Tanith, who politely [[spoiler:wiped out the Tollans]].
* SomeKindOfForceField: Several varieties of force fields appear in the series, with various visual effects revealing their presence. Most of them are indeed invisible unless touched, but the results of a contact are quite variable.
** In "Upgrades", the Goa'uld forcefields inside a ship in construction glow blue and look somewhat like frost on windows when touched -- or when going through at SuperSpeed thanks to the Atoniek armbands.
** In "Deadman Switch", Daniel Jackson walks nose-first into a red-glowing forcefield, put in place by Aris Boch to capture SG-1. Later in the episode, Teal'c is encased in a smaller version of the same field used as a detention device, and "knocks" on it to show the audience it's there.
** In "Windows of Opportunity", a forcefield surrounding Malakai and the Ancient control device doesn't just glow when hit: a mere contact propels Teal'c backwards and knocks him out. When the team tests the field again by throwing a stone at it, it shoots back with the speed of a bullet.
** In "The Other Guys", SG-1 is imprisoned in a forcefield that glows bright white on contact -- as well as giving a serious shock when touched, if O'Neill's reaction is anything to go by.
--->'''O'Neill:''' [[CaptainObvious Don't touch this...]]
** In "The Ties That Bind", the power coil-slash-religious device is protected from thieves by a small forcefield, invisible until Daniel touches it, stinging his fingers. DVD commentary reveals it was a ThrowItIn by Michael Shanks; although not planned in the script, the special effect was added afterward.[[invoked]]
* SomethingOnlyTheyWouldSay: In "Crystal Skull", O'Neill starts to believe that he really is talking to Daniel when Nicholas Ballard responds to one of his flippant remarks with "Jack, don't be an ass."
* SoProudOfYou: In "Talion", Bra'tac explains that Teal'c is [[LikeASonToMe like a son to him]] and that he is very proud of what he has accomplished.
* SortingAlgorithmOfEvil: The series started with Apophis. When they finally got rid of him, even stronger Goa'uld showed up. But that's okay, the team got good at dispatching Goa'uld. So Anubis shows up, with the full knowledge of the godlike beings who had created the Stargates. But they took care of him -- though it was a close one. For almost a whole month there is peace. Then the godlike Ori turn up.\\\
This progression is grounded in the plot by the Tok'ra. They say that every time the Tau'ri defeat a System Lord, an even worse one inevitably takes advantage of the power vacuum. By killing Ra, and others, SG-1 kept disrupting the Goa'uld balance of power, allowing more aggressive Goa'uld to sweep up now-leaderless forces and rise in threat level. They didn't cause Anubis, but probably sped up his timetable. They did make the Replicators more dangerous, by giving the nanotech precursor of the Replicators to the Asgard, from whom it was then captured. In a self-application of UnwantedAssistance, the Ori only found out about the Milky Way galaxy when Daniel Jackson and Vala accidentally warped over to their home galaxy and caused a scene. An unfortunate coincidence, perhaps, but still their doing.
* SoundEffectBleep:
** In "Heroes", O'Neill goes on a tirade against Senator Kinsey, most of which is drowned out by the alarm announcing an incoming wormhole. Judging by mouth movements, situation, character, Kinsey's expression, and the timing of the intercom's interruptions... the rest was very rude.
--->'''O'Neill:''' You smarmy, self-righteous, opportunistic ass--\\
'''Intercom:''' ''[with siren]'' Unscheduled off-world activation.\\
'''O'Neill:''' You're nothing but a l--\\
'''Intercom:''' Repeat, unscheduled off-world activation.
** In another episode, Sam Carter refuses to ask out another female staffer on Jonas Quinn's behalf, telling him, "You are such a chickensh--" before getting cut off by an alarm.
* SpaceColdWar:
** The Asgard and the Goa'uld prior to the series, whose relations are governed by the Protected Planets Treaty. This treaty forbids Goa'uld invasion of certain worlds, and requires that the Goa'uld as a whole stop any rogue Goa'uld from doing so, but simultaneously acknowledges that humans exist to be hosts for the Goa'uld, and thusly are to have limited technology so as to never pose a threat to the System Lords. When Jack O'Neill questions why the Asgard stand for such a thing, and why they even allowed the Goa'uld to gain such power in the first place, Thor explains that the treaty is actually a complete bluff. The Asgard are so occupied fighting the war with the Replicators that they do not have the resources to actively combat the Goa'uld, forcing them to accept this "peace".
** Langara prior to "Homecoming" was engaged in a cold war between the three dominant superpowers. When two of those superpowers [[EnemyMine ally]] in "Shadow Play", the third, Kelowna, launches a preemptive strike with a naquadria bomb. This terrifies all combatants enough to prevent further hostilities [[spoiler:until Anubis arrives and renders their internal conflicts moot.]]
** In "Icon", the cold war on Tegalus between the Rand Protectorate and Caledonian Federation is disrupted by SG-1's arrival, which allows a religious extremist faction to rise up in Rand, eventually overthrowing the government and starting a war which reduces most of the continent to rubble. The SGC helps the Rand loyalists regain control, but the international tensions remain into season nine's "Ethon", when the Ori give the Rands a KillSat.
* SpaceFighter:
** Notable in that the [[ScaryDogmaticAliens villains]] have space fighters from the very start, but the good guys have to develop theirs slowly over several seasons. As with most of Goa'uld technology, their Death Gliders are [[CoolButInefficient more impressive than practical]].
** The F-302, the USAF finalized space fighter design, takes many of the Glider's systems and adds all the trappings of a modern jet fighter (missiles, ejector seat, autopilot, etc.). The prototype, the X-302, also had a naquadriah-powered hyperspace generator, but the instability in the naquadriah meant that it could not function as a means of transport and was removed from the standard production model.
** The Ori crusaders have space fighters too, which easily curbstomp Death Gliders.
* SpaceIsAnOcean: Partially averted, with space travel being in the hands of the Air Force. Most of the trappings of this trope are there, but they specifically avoid naval terminology; they use missiles instead of torpedoes, almost nobody says "port" or "starboard", the ships are flown by a pilot instead of a helmsman, etc. At the same time, given the size and purpose of the larger craft, it is apparently acceptable to refer to BC-303s and BC-304s (which ''do'' kinda look like flying aircraft carriers) as ''Prometheus''-class and ''Daedalus''-class '''ships''', respectively.
* SpaceMines: "The Serpent's Venom" takes place in a space minefield where the mines all lock onto any sign of weapons, which is used by the Goa'uld as a neutral meeting place. SG-1 has to reprogram a mine to attack one of the Goa'uld ships at the meeting in order to instigate a conflict.
* SpaceshipSlingshotStunt:
** A slingshot maneuver around Jupiter is attempted by O'Neill and Teal'c to get the X-301 turned around in "Tangent", but the attempt fails as the rockets they are using, the pair of Sidewinder missiles the 301 is equipped with, lack thrust.
** In "The Pegasus Project", the ''Odyssey'' successfully pulls one around a black hole, after goading a Wraith Hiveship to follow them. They make it, while the Hiveship has no such luck due to the ''Odyssey'' using the fact that the black hole is disrupting their systems to beam a nuke inside the ship.
* SpannerInTheWorks: The security guard in "Bad Guys" makes things harder for both SG-1 (who are mistaken for terrorists) and the negotiators who are trying to get the hostages free. Though, as the episode is a WholePlotReference in the form of [[DieHardOnAnX Die Hard in a Museum]], this was inevitable.
* SpecialEffectBranding: The show gives each major player their own radically different ship design and weapon effects, ranging from Egyptian pyramids to Earth naval ships to bioships, though there is an exception: the minor races all use the same (Goa'uld) design of ship, having acquired them second hand. That said, the technology of both humans and aliens in the Pegasus Galaxy of ''Series/StargateAtlantis'' looks quite different. Even the gates are of a different design. And despite their obvious usefulness, the Atlantis team does not appear to have brought any Zat guns or staff weapons with them, nor have they sent any Wraith stunners or (with one temporary exception) puddle jumpers back home.
* SpecialGuest: The US Air Force really likes this show. Enough that Generals and USAF Chiefs of Staff Michael E. Ryan and John P. Jumper made guest appearances as themselves.
* SpitTake:
** In "Avenger 2.0", SG-1 {{fanboy}} Dr. Felger does a spit-take when Major Carter announces to him that they'll work together on his new project.
** In "Ripple Effect", Colonel Mitchell gets into a rather animated conversation (with himself) about "the spit-take of all spit-takes."
* SpockSpeak: Teal'c. "Indeed."
* StalkingIsLove: Averted. Orlin claims that he loves Carter, but she explicitly points out that he is stalking her, and what they have is not a "relationship". She does warm up to him eventually, and even grows to like him, but she never falls in love with him in return.
* StandardSciFiArmy: Typical for television, the military forces are limited to infantry. Considering the Stargate limits how much can go through, it's justified.
* StandardStarshipScuffle: Increasingly frequent once the Tau'ri got {{Cool Starship}}s of their own.
* StarKilling:
** Samantha did this in "Exodus", [[RememberWhenYouBlewUpASun and got a trope named for her.]]
** In "Red Sky" Carter nearly did this ''by accident'' when the wormhole passed through a star and poisoned it with heavy elements.
** At some point prior to "New Order", the Asgard collapse Hala's sun into a black hole to try and kill the Replicators.
* TheStarscream: Ba'al, the most free-thinking and adaptable of the System Lords, rises from obscurity to become not just the most powerful one, but ''the only one left''.
* StaticStunGun: the Zat'nik'tel, or "Zat Gun" as O'Neill dubs it. Functionally a Goa'uld/Jaffa "sidearm", it is stylized like a serpent preparing to strike when in safety, and jumps out like a striking serpent when prepared to fire. The SGC commandeers many over the course of its operations and makes use of them too, with some SG team operatives preferring them for sidearms over the conventional 9mm service pistol. It's not entirely a non-lethal weapon; the first shot stuns. If the target is shot with a Zat a second time shortly after, odds are good that it was lethal. A third shot vaporizes the target. The electrostatic effect of its shot has been used for some alternative means other than to non-lethally incapacitate the target.
* StatingTheSimpleSolution: When O'Neill was serving as a [[BackedByThePentagon technical advisor]] for ''Wormhole X-Treme!'' he overheard the executives debating how to have the character get past a giant alien guard, since budget constraints meant that they would need to re-write the previous plan of having him be weightless. When O'Neill asks [[WhyDontYaJustShootHim why he does not just shoot the guard]], they decide to go with that.
* StayWithTheAliens: Daniel's grandfather Nicholas Ballard in "Crystal Skull".
* SterilityPlague: In the BadFuture portrayed in "2010", the Aschen plan to surreptitiously conquer Earth involves one of these, distributed under cover of advanced medical tech. As shown in the later episode "2001", this is their ''modus operandi''.
* StockFootage:
** The gate dialing and opening, most often. Sometimes subverted with powerful effect when things go wrong.
** Heru'ur's ship landing on Abydos in "Secrets" is actually footage from the ''Film/{{Stargate}}'' movie, played backwards.
** "Touchstone" uses stock footage of a C-5 Galaxy landing, easily recognizable as such due to it being much more staticky than usual.
** Vala's ''Wizard of Oz''-inspired story in "200" reuse footage of the cargo ship crashing from "Last Stand".
* StoryArc: At least one per season.
* StrangeMindsThinkAlike: General Landry has a habit of quoting famous historical generals, and he is in turn occasionally quoted by Colonel Mitchell. In "Counterstrike", Mitchell repeats a quote Landry has given, explaining it came from [[Literature/TheArtOfWar Sun Tzu]], but he then amended that Landry might have actually been repeating [[Series/DoctorPhil Dr. Phil]] that time. In the next scene, when Landy provides a different quote to Bra'tac, who praises the wisdom of the warrior who provided it, Landry said that that time he ''was'' quoting Dr. Phil.
* StrangeSyntaxSpeaker: Briefly, O'Neill in "Lost City".
-->'''Daniel:''' ''[in the grip of a translation {{eureka moment}}]'' Sphere. Planet. Label. Name.\\
'''Jack:''' Following. You. Still. Not.
* StupidEvil: The Goa'uld; in "In the Line of Duty" Teal'c explains that he has seen certain victory turn to defeat simply because the Goa'uld cannot rein in their [[EvilGloating gloating]] or [[ForTheEvulz pointless sadism]].
* StupidSacrifice: Averted by O'Neill. After successfully destroying the shield system on an invading Goa'uld mothership, they ponder their next move. The following dialogue occurs:
-->'''O'Neill:''' Now what?\\
'''Bra'tac:''' Now, we die.\\
'''O'Neill:''' Well, ''that's'' a bad plan. Where's the glider bay?
* StyrofoamRocks:
** Played straight in "The Gamekeeper", which seemingly reveals that Daniel's parents died by being crushed inside an ancient cardboard temple.
** Parodied in "Wormhole X-Treme!" and [[DiscussedTrope discussed]] in the {{Troperiffic}} "200", in which an actor on the ShowWithinAShow complained about the career choices that led to him being pelted with StyrofoamRocks.
* SufficientlyAdvancedAlien:
** Despite the standard Goa'uld procedure of posing as a deity in order to rule a conquered people, [[AvertedTrope the technology of the Goa'uld does not qualify as Sufficiently Advanced]] as visible technology is directly connected to all accomplished feats.
** The Nox, introduced in the self-titled episode "The Nox", possess the ability to raise the dead, teleport from point to point, activate a Stargate with a wave of the arms (no DHD needed) and become intangible/invisible at will. They accomplish these feats with woodland rituals, symbolic gestures and a philosophy which emphasize nature and pacifism. The end of their introductory episode reveals that they do ''have'' a technological city, but their skills and abilities do not visibly derive from it.
** The [[NoNameGiven unnamed aliens]] masquerading as the divine spirits of a group of Salish-descended people have the ability to change their shape and image, communicate telepathically and make people appear/disappear. This is accomplished with only a wave of their arms and is effective across interstellar distances.
* SuperCellReception:
** The episode "Threads" has Carter's cell phone ring in the SGC briefing room. The briefing room is 28 floors underground inside a mountain. (See also RuleOfFunny, given that she thought she had it turned off.)
** In "200", Martin Lloyd complains that his cell reception is terrible in the SGC briefing room. As above, the fact that he gets any signal at all is a miracle. Again, RuleOfFunny may be in play given the mostly parodic nature of the episode.
** Justified. The real Cheyenne Mountain Complex has over 700 repeaters in it to enable cell phones to work. In-universe, the SGC is located on a fictional sublevel 28 of that complex, but the complex itself is real and cell phones do work there.
* BadassAdorable:
** The Nox, the race that inspired the fairytales of Earth, are the cutest, sweetest, nicest, committed pacifists you will ever meet. Throughout the series, anyone who messes with them is met with a resounding and unequivocal defeat.
** Heimdall of the Asgard is the friendliest of an already likeable species. She's cool as a cucumber while under siege by the Goa'uld, defending the very future of her species, and trying to rescue Supreme Commander Thor all at the same time.
* SuperpowersForADay: The human members of SG-1 gain extreme strength, speed and senses while wearing the Atoniek armbands. They have the ability to kick through solid concrete, move faster than the human eye and see in almost complete darkness. They can even see the modulations of Goa'uld forcefields, and run so fast that they can go through them. Unfortunately, [[WithGreatPowerComesGreatInsanity their judgement is compromised at the same time]].
* SuspiciouslySimilarSubstitute:
** The trope was originally named "Jonas Quinn", after Daniel Jackson's replacement in season six when actor Michael Shanks left the show.
** Lieutenant Colonel Cameron Mitchell was added to the cast in season nine as a replacement for Jack O'Neill with the same humorous personality. [[YouRemindMeOfX Teal'c even commented that he reminded him of O'Neill]].
** Colonel Emerson and the ''Odyssey'' for Colonel Pendergast and the ''Prometheus'' after [[spoiler: they are destroyed]]. Emerson himself was replaced by Colonel Davidson after [[spoiler: Emerson was murdered by the Lucian Alliance]].
* SuspiciouslySpecificDenial: When the pilot was ReCut into a DTV movie, Carter's infamous "reproductive organs" line was removed in order to give the character more natural dialogue. Unfortunately, O'Neill's response is kept intact, so in the new film, instead of refuting an accusation that he is sexist, he instead brings up her gender apropos of absolutely nothing.
* SwordFight: Mitchell fights two of Merlin's holographic knights in season nine: The first is more of a [[OnlyTheWOrthyMayPass test]] than an actual enemy, and he manages to defeat it [[HeroicResolve after gaining a new determination]], but the second is a security device that is about to kill him when Daniel [[BigDamnHeroes comes to his rescue]].
* TheSymbiote:
** Goa'uld and Tok'ra straddle the line between mutualism and parasitism. The host gains an extended lifespan, HealingFactor, and boosted strength, while the symbiote gains a body with hands and a voice. On the other side, the symbiote can also take over the host body completely; the difference between Goa'uld and Tok'ra is mainly the conscious choice whether or not to do this. The Tok'ra also only take volunteer hosts.\\\
The fact that the Tok'ra sometimes break their own rules in this regard muddies the waters. In their first episode, "In the Line of Duty", the Tok'ra Jolinar jumps hosts to Carter and takes her over (but she was desperate). In the second case, O'Neill was given a symbiote to save him from the Ancient plague in "Frozen". As a byproduct of the blending, the Tok'ra gained Jack's code of ethics, including NoOneGetsLeftBehind, so it took over his body and went to a Ba'al-controlled planet to extract someone who had helped him on a previous mission.
** Anubis is a full-on parasite. Having been kicked partway back down to the lower planes by the Ancients [[spoiler:to punish Oma Desala for helping him AscendToAHigherPlaneOfExistence]], he exists as an EnergyBeing that needs either a force-field suit (through "Lost City") or a host (season 8) in order to interact with our world. The host has no control over their body and treats Anubis like an infection, breaking out into lesions and eventually suffering immune system failure.
* SympatheticMurderBackstory: In "Collateral Damage", Cam recalls a mission in the Middle East during which he bombed what he believed to be enemy targets only to learn that they were a convoy of refugees.
* TakeAThirdOption: In TheTeaser of "Proving Ground", this is actually the correct solution. The end of the training scenario has Sam holding Daniel at gunpoint, each claiming the other is a Goa'uld. In Lt. Hailey's words, the solution is to zat them both and sort it out later.
* TakeMeToYourLeader: Jack O'Neill uses this sometimes. Inverted in that he's a human speaking to aliens on their own planet. There's also an element of IAlwaysWantedToSayThat to it.
* TakeThat:
** In "Politics" Daniel mocks the idea of regular US military forces taking on the Goa'uld by saying that sure, they will just [[Film/IndependenceDay upload a virus into the mothership.]]
** In "Orpheus", Carter discusses seeing the movie ''Film/{{Signs}}'' and is incredulous that the alien's weakness was water. When Daniel asked her why she even watches science-fiction if she is just going to tear it apart, she mentions that she wants to see if they are getting it even close to right.
** In "The Scourge", Mitchell explains that the team is going to watch ''Film/StarshipTroopers'' for movie night since they spent the episode [[BugWar fighting a horde of alien insects]]. Teal'c, who had been planning to watch ''Old School'', asks if the movie is humorous, to which Mitchell responds, "[[SoBadItsGood Is it ever.]]"
* TakingTheBullet: In the second episode of season 7, Jonas Quinn takes a staff weapon blast aimed at Daniel Jackson, expiating for having caused Jackson's death (and ascension) at the end of season 5. He survives, though.
* TakingYouWithMe:
** The Alternate Samantha Carter of "There But for the Grace of God" lured in several Jaffa with the offer of valuable information for Apophis, then pulled out a grenade to take them out along with her.
** During the Battle of Antarctica in "Lost City", Hammond orders the ''Prometheus'' onto a collision course with Anubis' flagship, saying "We go, they go." [[spoiler:Subverted in that the weapons of the Ancient outpost get there first, and Hammond is only too happy to break off.]]
* TalkingToThemself: Since the Tok'ra share their hosts' bodies symbiotically rather than taking it over, this is known to happen. Before Selmak takes Jacob Carter as a host in "The Tok'ra, Part 2", Samantha remarks that once blended Jacob could spend hours cracking himself up. "Seth" includes Selmak saying Jacob has unfinished business with his son Mark, then Jacob immediately contradicting him.
* TantrumThrowing: Cameron gets frustrated and trashes his room in "Unending" from being locked in the time-stopped ship for so long.
* TastesLikeChicken: In "The First Commandment", SG-1 is sitting around a campfire eating [=MREs=].
-->'''Daniel:''' This tastes like chicken.\\
'''Sam:''' So what's wrong with it?\\
'''Daniel:''' It's macaroni and cheese.
* TastesLikeFriendship: Daniel feeds random alien, random alien becomes his friend.
-->'''Daniel:''' [[ContinuityNod You know, it's funny]], [[Film/{{Stargate}} I met my father-in-law like this...]]
* {{Technobabble}}: Mostly courtesy of Carter, [=McKay=], and a couple of others. O'Neill serves as a bit of a GreekChorus when this happens, either interrupting Carter to ask a simple "yes or no" question, or else to irritatedly inform her that he ''does'' know what photosynthesis or supernovas are, thank you.
* TechnologyUplift: A frequent dilemma for the more advanced races is whether or not to do this. Most races are reluctant to provide Earth any advanced technology due to either bad prior experiences, such as the Tollan who in the past gave a lower-tech planet an unlimited energy source only for them to blow themselves, or believing Earth is not yet mature enough as a civilization. The main exceptions are the Asgard, who owe Earth, and the Tok'ra, with whom Earth was in an alliance. A episode also features the Aschen, a race that ''appear'' to do this but are doing so for their own ends.
* TeleporterAccident: "Solitude"; "1969"; "48 Hours"
* TeleportersAndTransporters: The Stargates and ring transport platforms inherited from the movie are the most common. The Asgard bring the ''Franchise/StarTrek''-style "beams" into play.
* TeleportInterdiction:
** The iris is used to prevent anything unwanted from coming through the Stargate.
** As in many other settings, deflector shields block teleportation, and Ori motherships apparently have systems to prevent explosive devices being ringed aboard when the shields are dropped to fire the main cannon (the ''Korolev'' and ''Odyssey'' try it at the supergate battle in "Crusade", and Bra'tac tries it again later in "Flesh and Blood", and neither attempt is successful).
** Subverted in "The Pegasus Project". The ''Daedalus'' is able to [[spoiler:beam a warhead aboard a Wraith hive ship]] because the black hole is disrupting the countermeasures [[spoiler:the Wraith]] have against Asgard teleporters.
* TemporaryLoveInterest: Several.
* TerminallyDependentSociety: Jaffa carry a larval goa'uld symbiote in their stomach pouches, which grants them an increased lifespan and immunity from disease, but suppresses their own immune system. If the symbiote is removed, they grow ill and die within days. In season six the Tok'ra discovers the medicine tretonin, which can replicate the healing effects of the Goa'uld, but this simply transfers the dependency to an artificial chemical. However, tretonin is a manufactured substance, and the means of production aren't hung over them as a means of control like the Goa'uld's use of them as incubators was. Means of production could easily be taught to them to put that aspect of their liberty in their own hands.
* ThatManIsDead: At the conclusion of "Cor-ai", Hanno, who has spent the episode trying to get Teal'c executed for killing his father, allows him to go free after Teal'c had helped save him and his people from the Goa'uld. When Teal'c asks why, since he ''did'' kill his father, Hanno explains the he did not, as the Jaffa who did is dead, and Teal'c killed him.
* ThemeNaming: Earth's starships tend to follow this convention. The American-crewed vessels are named after mythological figures (the exception being ''Series/StargateUniverse'''s ''George Hammond'', which was renamed from the ''Phoenix''), while the Russian- and Chinese-crewed vessels tend to be NamedAfterSomebodyFamous.
* ThemeTuneCameo:
** Carter is humming the ''SG-1'' theme song in the elevator in "Chimera". [[WhatCouldHaveBeen She was originally going to hum the theme to]] ''Series/MacGyver'', but neither she nor anybody else on set could remember how it went.
** During the wedding scene in "200", the organ is playing a combination of Mendelssohn's Wedding March (the "standard" wedding composition) and the show's theme.
* TheyCalledMeMad: Daniel Jackson and his grandfather, plus several different scientists encountered off-world who were studying their respective Stargates and/or artefacts [[AncientAstronauts left behind]] by the various alien cultures.
* TheyLookLikeUsNow
* TheThreeFacesOfAdam: Ry'ac, Teal'c, and Bra'tac have such a dynamic. Ry'ac is the Hunter, trying to define himself and live up to the fame of Teal'c, his father. Teal'c is the Lord, once a Jaffa in a lofty position as First Prime of a System Lord and now a lynchpin of their new society as the first jaffa to so brazenly defy their Goa'uld overlords and call out the fallacy of their divinity. Bra'tac is the Prophet, the one who instilled such beliefs in his protege, Teal'c, and sits back to watch Teal'c fundamentally change Jaffa society while still giving counsel to Teal'c when asked.
* ThroatLight: When a person is being tortured with the Goa'uld [[AgonyBeam cattle-prod device]], light shines out of their mouths and eyes. Richard Dean Anderson did not like this visual effect, and would close his eyes whenever Jack O'Neill was being tortured in order to keep it from being used.
* ThrowingYourSwordAlwaysWorks: In "Thor's Chariot" one of the Cimmerians kills a Jaffa [[ArmorIsUseless through his armor]] with a thrown battleaxe to the chest.
* TidallyLockedPlanet: The Planet of the Week in "The Broca Divide" was tidally locked with its sun so one side was always light, the other always in darkness. The civilization lived in the light side near the terminator, where it was temperate. A plague that made humans devolve into Neandertalesque creatures had broken out, and the infected were banished to the dark side of the planet. The gate happened to be in the darker parts of the terminator.
* TimeCompressionMontage: "Unending", the series finale, had one of these, set to Creedence Clearwater Revival's "Have You Ever Seen the Rain?"
* TimeForPlanB:
** O'Neill likes to poke fun at this line.
--->'''Reynolds:''' Not much faith in Plan A?\\
'''O'Neill:''' Since when has Plan A ever worked?
** Another time:
--->'''O'Neill:''' It's time for Plan B.\\
'''Carter:''' We have a Plan B?\\
'''O'Neill:''' No, but it's time for one.
* TimeTravel: Multiple times, including alternate timelines.
* TimeTravelEpisode: In the episode "1969", SG-1 ends up in the 1960s when a solar flare intercepts with an active wormhole.
* TimeTravelersAreSpies: In "1969".
* TitleDrop: Quite apart from the fact that there's one every time somebody mentions SG-1, the individual episodes include their own titles in dialogue very frequently.
* TomatoInTheMirror: In "Tin Man", where after visiting the ruins of a technologically advanced society, the team comes back through the Stargate only to discover that they are robot copies of the originals.
* TomboyishName: Samantha "Sam" Carter. In the pilot O'Neill [[SamusIsAGirl mistook her for a man]] when he was told that Sam Carter was their foremost expert on the stargate, and in a later episode when is asked what her name means, she responded that it means her dad wanted a boy.
* TooCleverByHalf: Anubis is this when he takes Thor Prisoner. He implants a device in Thor's frontal lobe to download his knowledge into the ship's computer. Thor uses the connection to take over plot-critical ship functions.
* TookALevelInBadass: Daniel takes several levels in badass over the course of the series.
* TookALevelInJerkass:
** Daniel goes from a charming NiceGuy to a manipulative handsome devil with aggressive urges, after his repeat exposure to a Goa'uld sarcophagus whilst being uninjured, causes him to become addicted to its effects. It lasts only one episode, as he quickly is forced to go cold turkey.
** Daniel again, when Shifu grants him a vision of [[HeWhoFightsMonsters what he'd become]] if he gained all the knowledge of the Goa'uld.
** After gaining their independence from the Goa'uld in "Threads", the Free Jaffa Nation spend most of Series 9 and 10 being a group of {{ungrateful bastard}}s to their former allies, treating the Tau'ri and the Tok'ra with open suspicion and mistrust and downplaying their vital role in the fall of the System Lords at nearly every turn.
** A great example of the latter occurs in "Ex Deus Machina", where the Jaffa don't see anything wrong with repeatedly infringing upon Earth's sovereign territory to apprehend Ba'al, nearly blowing the masquerade wide open in the process. In comparison, whenever the Tau'ri venture to Dakara, they attempt to be diplomatic and respectful and when it's made clear that they've outstayed their welcome, they ''leave!''
* TortureIsIneffective: In "[[Recap/StargateSG1S10E17Talion Talion]]", Teal'c tortures a man involved in several bombings against the Free Jaffa Nation but gets little useful information (admittedly he was doing it partly to punish him). In prior episodes his technique of sitting across the table from the prisoner and simply [[DeathGlare glaring at them until they talk]] was a hell of a lot more effective.
* TouchedByVorlons: Daniel, Anubis, Priors, Carter and O'Neill.
* TrainingMontage: Teal'c puts his neighbor through one in "Affinity".
* TrailersAlwaysSpoil: Every episode ends with a brief "OnTheNext" montage, often including clips from the later parts of the next episode, with much potential for spoiling potential twists and turns. (And unlike many examples of the OnTheNext trope, these previews are included with the episode itself, and so are seen every {{rerun}}, too!) Made better by the show's tendency to subvert or play with common sci-fi tropes -- even if you know a twist is coming, you don't necessarily know exactly how the show will play it.
* TranquillizerDart:
** In season 1 episode "Hathor", tranquilizer guns are used against the entranced SGC guards to neutralize them non-lethally.
** The Salish Indians in episode "Spirits" take out SG-1 with blowpipes firing tranquillizer darts.
** In "Redemption, Part 1", Captain Hagman (the 9th temporary replacement for Daniel Jackson) gets hit while SG-1 is ChasedByAngryNatives.
** Osiris is twice shot by a tranquillizer dart tipped with a Goa'uld-specific sedative. The second time, this leads to her capture.
** SG-1 later uses a trinium tranq dart tipped with the same sedative to try and subdue a Kull warrior. It penetrates the armor, but doesn't even slow it down.
* TranslationConvention: The episodes "Summit" and "Last Stand" are explicitly stated to be spoken in Goa'uld, but all the dialogue is in English for the convenience of the audience. Several other episodes have dialogue that is implied to be the same, particularly when aliens speak amongst themselves.
* TranslatorMicrobes: Though never mentioned in the show, [[AllThereInTheManual the novels based on the series]] reveal that the Stargates somehow allow people from different planets to understand one another. The characters themselves do not understand how it works, nor why it works sometimes but not others, but it explains why almost all the [[AliensSpeakingEnglish aliens speak English]]. Although one could speculate that this ''might'' have something to do with the fact that Earth's Stargate operates with a jury-rigged together dialing device, which ignores about 200 or so command signals that it's ''meant'' to use during operation. It's possible whatever causes this effect on their own Gate has been left a little bit iffy as a result.
* TransplantedHumans: The majority of the inhabitants of the Milky Way are humans that the Goa'uld transplanted from Earth to serve as their labor force. The name used throughout SG-1 to refer to the people of Earth, "Tau'ri", translates as "those of the first world", since Earth is where everybody else originally came from.
* TrialByCombat: The Jaffa believe firmly in the concept of AsskickingEqualsAuthority; if a Jaffa believes that he is more worthy of leading than the Jaffa in charge he may challenge him to ritual combat for the position of leader.
* TrueCompanions: SG-1, of course.
-->'''Samantha Carter:''' We were a team. No one else can even ''begin'' to understand what that means.
* TwentyOneGunSalute: The episode "2010" has a 21-gun salute as part of a ceremony commemorating SG-1 and their contact with the Aschen ten years before in an AlternateTimeline.
* TwoKeyedLock: Sometimes it is passwords, sometimes it is keys.
* TwoOfYourEarthMinutes: In "Beachhead", Mitchell explains to a Prior that their bomb will detonate in thirty "Earth minutes." When Daniel asks why he used the term, he explains that [[IAlwaysWantedToSayThat he always wanted to say that]].
* TyphoidMary: The Priors managed to sneak their plague onto the Earth by turning an SGC lieutenant into an asymptomatic carrier, passing through quarantine because he exhibited no signs of the disease before he began passing it on to civilians he encountered outside the base.
* TyrantTakesTheHelm: General Bauer in "Chain Reaction".

* UnCancelled: InUniverse, ''Wormhole X-Treme!'' was picked up for a movie in "200", five years after being cancelled after the third episode. Then the network dropped the movie and started the series back up again, and it ran for ten seasons before getting a green light on the movie again.
* UndeadTaxExemption: {{Justified|Trope}}.
** Five or six different offworld-born humans are granted asylum by the Stargate Program, as is a clone of O'Neill. As this is the United States government we're talking about, dummying up the papers wouldn't be much of an issue; the show specifically mentions in "Singularity" the backstory they gave Cassandra Fraiser.
** In season nine, Ba'al and a few minor Goa'uld turn up in control of several major Earth corporations. The answer is in how they got there: [[spoiler:by capturing and infesting The Trust in season 8, a group with powerful friends in the US government.]]
* UnflinchingWalk: Teal'c pulls this off in the episode "Talion".
-->'''Teal'c:''' I am leaving, you are about to explode.
* UngratefulBastard:
** SG-1 abandons Replicator Fifth to an eternal prison in a time bubble after Fifth betrayed his brethren to help them. This is heavily weighed before they follow their orders.
** After gaining their freedom from the Goa'uld, the Free Jaffa Nation engage in this a ''lot'' during Series 9 and 10.
* UniquePilotTitleSequence: "Children of the Gods" imitates [[Film/{{Stargate}} the movie]] with a long pan over the mask of Ra. After that, they used cut-together clips from season 1, changing it only when the main cast changed. The DVD releases of seasons 4 and 5 use the "Children of the Gods" title sequence for some reason.
* {{Unobtainium}}:
** The heavy metal naquadah, which is the material the Stargate is composed of, does not naturally exist within the Solar System and is heavily involved in Goa'uld technology. Its nonexistence in the Solar System is a minor plot point in "Fail Safe". [[spoiler:Carter realizes that the asteroid they are trying to stop from hitting Earth has a core of naquadah, leading her to the conclusion that it was imported by the Goa'uld to circumvent the Protected Planets Treaty with a manufactured natural disaster.]] Naquadah can be converted to naquadria, a more powerful but unstable variant, when it is exposed to certain radiation.
** Trinium is a silvery metal that is very light and about a hundred times stronger than steel. The Tau'ri and Asgard use it in the hulls of ''Prometheus''-, ''Daedalus''-, and ''O'Neill''-class warships, while the Tollans combine it with other substances in several pieces of AppliedPhlebotinum (including the device that lets them walk through walls). And the Tsalish use it for [[MundaneUtility arrowheads]].
* UnrealisticBlackHole:
** In "A Matter of Time", when a black hole forms from a pre-existing star, its gravity suddenly and inexplicably increases. An actual black hole's formation occurs when a star's mass collapses into a singularity, but its gravity doesn't suddenly increase as depicted in the episode: it has the same mass and gravity, just in a much smaller volume. It's indicated that the planet is falling towards the black hole at the time, which would at least partly explain the increasing effects. Carter actually [[LampshadeHanging acknowledges]] that she has no idea what's going on with it.
** {{Conversed|Trope}} in "200":
--->'''Sam:''' "The singularity is about to explode"?\\
'''Martin:''' Yes.\\
'''Sam:''' Everything about that statement is wrong.
* UnresolvedSexualTension: Carter and O'Neill. WordOfGod states that just about the nanosecond Jack retired, he and Sam got it together and got it on. (Alternatively, [[WordOfGod Word of a Different God]] states that they got together after "Threads" and have merely kept the relationship quiet ever since.) A deleted scene from the ''Series/StargateAtlantis'' episode "Trio" also pretty much confirms that it finally got resolved.\\\
This causes the pair to be mistaken for brainwashed assassins in "Divide and Conquer", when a Tok'ra LieDetector gets a false positive because they [[spoiler:do not admit the real reason he would not leave her behind on the previous mission.]] The writers play with this hilariously in "Window of Opportunity". During one timeline cycle, since neither Carter nor, more importantly, General Hammond, will remember it after the timeline resets, O'Neill resigns his commission so he can finally kiss Carter.
* UnsettlingGenderReveal: Inverted. Daniel looks rather ''relieved'' when the Kull Warrior who has him tied up in "Prometheus Unbound", who said Daniel was the "most attractive" human, turns out to be the human, and female, Vala.
* TheUnsmile: In the first season, when Teal'c is still getting angry looks for being a Jaffa, Daniel explains that he is a friend and tells him to smile. The resulting facial movement is... [[http://www.youtube.com/watch?v=F9oByzdOQOA off.]]
* UnusualEuphemism: "I told her that she should attempt procreation... with herself."
* UnusuallyUninterestingSight: The team often walks right into settlements with guns at the ready. Rarely does anyone seem to have any trouble with this, though it does pop up when the plot demands it.
* UnwantedRescue: In "The Other Guys", SG-1 allowed themselves to be captured on purpose in order to make contact with a Tok'ra that was undercover as a Goa'uld working for Anubis. They are somewhat perturbed when Coombs and Felger stow away aboard their prison ship in order to rescue them.

* VichyEarth: The Aschen supposedly invite the Earth's peoples to join an [[CrystalSpiresAndTogas advanced alien confederation]]. The whole subsequent genocide and sterilization plot is secret from everybody except for the highest Aschen and some collaborating human leaders.
* VictoriasSecretCompartment: Vala, who else?
* VillainBall: The Goa'uld, the Ori, the Lucian Alliance, even Tau'ri factions like the NID all juggled it from time to time. See examples in the trope page.
* VillainPedigree: The Ori and Replicator pull this on the Goa'uld.
* VillainsBlendInBetter:
** Averted with Machello in "Holiday". He's technically not evil, but he ''is'' the antagonist of the episode. His attempts to blend into American society don't entirely work, with the homeless man he befriends convinced he's a Gulf War vet suffering from severe PTSD.
** Played straight with Ba'al. After his defeat in season 8 he eventually turns up on Earth, undetected and fairly successful. ("Fairly successful", as in ''the CEO of a major corporation''.) He blends in so well the only reason the [=SGC=] finds out about him is he intentionally exposes himself.
* VirtualRealityInterrogation: Season 2, episode 22 is a ClipShow where one of the plotlines is where O'Neill, Carter and Daniel awaken from stasis in what appears to be the SGC, almost 79 years in the future. They discover it is actually a Goa'uld hoax by Hathor.
* VoiceOfTheLegion: The deep, booming Goa'uld voice.
* VomitingCop: In "Enemy Mine", [[MauveShirt Major Lorne]] vomits after finding the body of one of his men killed by a Unas.

* WasntThatFun: Used in the ninth season; after the team has posed as drug dealers, been captured by drug dealers, got beaten up, captured by the Lucian Alliance, etc., they finally get back to Earth.
-->'''Mitchell:''' We have the best jobs in the world.\\
'''Sam:''' I'm going to hit the showers. ''[exits]''\\
'''Daniel:''' I'm going to find the doctor. ''[exits]''\\
'''Teal'c:''' We are indeed suitably employed, Colonel Mitchell. ''[exits]''\\
'''Mitchell:''' Yeah, good day.
* WastelandElder: Several, usually one per [[AdventureTowns Adventure Town]]-- err, planet.
* TheWatson: Jonas Quinn joins the cast in Season 6 from an alien planet, requiring him to be filled in on past SGC missions and esoteric parts of Earth history. This was particularly helpful since Season 6 is the season where they begin connecting and expanding on a lot of previously introduced continuity, primarily the concepts of Ascension, the Ancients and the greater society of the Goa'uld, so he could help bring new viewers up to speed. Season 6 is also when the show [[ChannelHop hopped]] to [=Sci-Fi=], making it more important to fill in viewers who hadn't seen it on Showtime.
* WeaponOfXSlaying:
** The first is the energy weapon for killing Anubis' [[SuperSoldier Kull warriors]], which is of indeterminate use against anything else but will kill Kull in a couple shots by negating the Ancient phlebotinum that brought them to life in the first place.
** The second is the Replicator disruptor (and the anti-Replicator gun adapted from it in ''Series/StargateAtlantis'' to fight the Asurans), a weapon built using Ancient knowledge that disrupts the ability of individual Replicator blocks to communicate with each other.
** The most impressive one, though, is certainly the Sangraal (the HolyGrail itself), designed by Merlin to wipe out ''all the ascended beings from a galaxy''. It is finally used on the Ori in season 10 episode "The Shroud", but it isn't before the movie ''Film/TheArkOfTruth'' that its efficiency is confirmed.
* WeCanRuleTogether: Nirrti attempts this with Jonas Quinn in "Metamorphosis" once she realizes he is her best shot at creating a Hok'tar (an advanced host with PsychicPowers). Jonas' response to the offer is that, if he was given such powers, the very first thing he'd do would be to destroy Nirrti.
* WeHaveForgottenThePhlebotinum: Several episodes deal with the team needing something from another base, planet, or needing a bit of [=MacGyvering=] to make a new doohickey, to solve whatever problem they're currently facing.
* AWeightyAesop: Used in a throwaway scene in season 6. As the season begins, alien refugee Jonas Quinn is shown eating in nearly every scene at the SGC. He later mentions to Carter that he's really gotten into this "traditional all-American food". Carter points out to him that America has another tradition: hardened arteries. This aspect of Jonas' character was quietly dropped after that.
* WeWillUseManualLaborInTheFuture: Justified for the the Goa'uld, who keep most of their human slaves in MedievalStasis to prevent rebellion. Generally averted by most of the other technologically advanced civilizations.
* WhamEpisode: In the episode "Heroes", the [[spoiler:death of Dr. Janet Fraiser]]. To add extra oomph, KilledOffForReal is played with in this episode, as two characters (including a RedShirt) receive potentially fatal wounds before it is revealed quite shockingly that [[spoiler:Janet]], whom the viewer does not even know got injured, is the one who actually died.
* WhamLine:
** From season 2, "Thor's Chariot", after only ever having encountered low-tech, hostile or extinct civilizations, Carter and Daniel come face to face with the hologram of a Grey and assume the same thing is going on...
--->'''Carter:''' ''[to a local]'' It's a hologram. It was probably recorded a thousand years ago, it can't hear you.\\
'''Thor:''' [[FirstContact On the contrary. My image is a living transmission.]]
** From 2.15 "The Fifth Race":
--->'''Carter:''' Sir, the computer indicates that [[spoiler:the wormhole is leaving our known network of Stargates. It's going outside of our galaxy. ''Far out.'']]
** From 3.13 "The Devil You Know Part 2":
--->'''Nao'nak:''' From this day forth I will reclaim my real name. ''[[[DramaticUnmask removes helmet]]]'' [[spoiler:Apophis]].
** In 8.18 "Threads", at the Astral Diner, a pathway to Ascension, Daniel Jackson has been conversing with Oma Desala and another ascended man named Jim who has periodically been providing him with information. Near the end Daniel asks Jim why he antagonizes Oma so much.
--->'''Jim:''' Who, me? I have nothing against Oma. I think she's great! [[spoiler:Hell, she's the one who helped me ascend.]]
** In the series finale, Thor asks permission to make modifications to the ship SG-1 met them in. Mitchell asks what technology they're getting this time:
--->'''Thor:''' Everything we have and know.\\
'''Mitchell:''' Everything, as in...?\\
'''Thor:''' ''Everything''.
* WhatHappenedToTheMouse: So many incidents that the show gets its own folder on the WhatHappenedToTheMouse/LiveActionTV subpage.
* WhatTheHellHero:
** "Shades of Grey", when Jack steals technology from Tollana. [[spoiler:Subverted when revealed to be a BatmanGambit to draw out the real thieves from the NID.]]
** "Unnatural Selection", where Jack [[IDidWhatIHadToDo made the hard call]] and was called on it by the team.
* WhatWeNowKnowToBeTrue: The Tollan have studied quantum physics... "among other misconceptions of elementary science". This doubles as FridgeBrilliance. The Tollan didn't state that quantum mechanics was a "misconception of elementary science", they stated the Copenhagen interpretation of quantum mechanics was the misconception (Sam was explaining the Schrodinger's Cat thought experiment, which was designed to show that the Copenhagen interpretation was ridiculous, to a Tollan). What's one of the alternatives to the Copenhagen interpretation? The Many Worlds interpretation. What does SG-1 do only a few episodes later? Visit an alternate reality, when they find the Quantum Mirror.
* WhatYouAreInTheDark: In "Window of Opportunity", as Daniel [[SarcasmMode helpfully]] points out, Teal'c and Jack are stuck in an infinite time loop and can do pretty much whatever they want without consequence. Over many "days" of this they get up to all sorts of wacky hijinx but nothing even remotely approaching despicable (well, maybe Teal'c shoving the door in that guy's face was a bit of a dick move).
* WhenThingsSpinScienceHappens: The Stargate itself, which has a center ring that spins when SG-1 is dialing. Interestingly, gates with functional [=DHDs=] don't spin, suggesting the spinning might be some sort of manual control. This is {{Lampshaded}} in the 200[-[[superscript:th]]-] episode during the marionettes parody sequence: as they are preparing to activate the Stargate for the first time, Gen. Hammond demands that they make it spin, as it is [[RuleOfCool so much cooler]] that way.
* WhereItAllBegan:
** The season six finale "Full Circle", the first season finale [[UnCancelled that was originally planned to be the series finale]], takes place primarily on Abydos, the planet visited in [[{{Film/Stargate}} the movie]] and the very first planet that SG-1 went to when the show began.
** "Moebius", which was also meant to be the series finale, revisited Ancient Egypt under Ra's rule, and Apophis's prison on Chulak from the pilot episode -- the alternate timeline SG-1 even got to recruit Teal'c again.
** Also the climax of ''Film/TheArkOfTruth'' takes place in the City of the Ori, a place that Daniel and Vala visited early on in the ninth season. While not the start of the show itself, it was the start of the Ori storyline.
** Within the show's story, when the Jaffa kicked the Goa'uld's asses once and for all, the final battle took place on Dakara and they chose Dakara as the capital of their new country; for the express reason that it was also the place where they first became slaves. It was also a significant religious site like Mecca is to Muslims.
* WhereNoParodyHasGoneBefore: In the episode "200", numerous other shows (mainly sci-fi) are spoofed when the SGC hires Martin Lloyd to produce the ShowWithinAShow "Wormhole X-Treme!" to maintain plausible deniability for the Stargate Program. One of the pitches he makes is for a blatant ''Star Trek'' rip-off (featuring the main actors in an ImagineSpot) that his audience complains is mostly TechnoBabble.
* WhoNamesTheirKidDude: Teal'c gets asked this regarding his own name in "Past and Present". He takes it in stride and answers that his father did, and that his name means "[[MeaningfulName strength]]".
* WhosOnFirst:
** The Goa'uld Yu resulted in some of this. Eventually, the joke wore thin and the only joke left was to state this.
--->'''Dr. Jackson:''' And the last one is Lord Yu.\\
'''Dr. Weir:''' Yu?\\
'''Dr. Jackson:''' Don't. Every joke, every pun, done to death. Seriously.
** After Ba'al starts cloning himself in the later seasons, Ba'al-related puns start to crop up.
--->'''Cam:''' We've got a full count, sir. Two strikes, three Ba'als.
* WhoWatchesTheWatchmen: Colonel Simmons of the NID explains the organization's mandate to O'Neill: Providing civilian oversight to top-secret military projects. Jack, however, wonders who oversees ''them''.
* WhoWritesThisCrap: When O'Neill summarizes his history to the memory-erased Martin, at the opening of act four, Martin comments that that is the worst Act Four Opener he has ever heard.
* WhyAmITicking: Cassandra
* WhyWontYouDie: Apophis has a habit of returning from supposed (and [[DeathIsCheap actual]]) deaths, much to the chagrin of SG-1.
-->'''O'Neill:''' ''[referring to Apophis]'' Somebody's gotta teach that guy how to die.
* WillTheyOrWontThey: In several episodes, the writers play with romantic tension between O'Neill and Carter, and two different AlternateReality versions of Carter are either engaged or married to O'Neill. The "won't they" wins out in the prime reality largely because for most of the show's run, O'Neill is Carter's direct superior and is thus barred from pursuing her by the Air Force's anti-fraternization rules.
* WinToExit: In "Avatar", Teal'c needs to defeat the simulated Goa'uld invasion of the SGC in order to [[HolodeckMalfunction leave the chair]], as the programmed exit feature [[FailsafeFailure is not functioning]].
* WireDilemma:
** In season 5 episode "Fail Safe", all the wires are yellow, so [[NoTimeToThink Jack has to guess which to cut]].
--->'''Col. O'Neill:''' I'd like to take this opportunity to say that [[LampshadeHanging this is a very poorly designed bomb]], and I think we should say something to somebody about it when we get back.
** In season 9 episode "Ripple Effect", an alternate-universe Cameron Mitchell tease main timeline Mitchell with "When the time comes, cut the green one."
* WiseBeyondTheirYears: Shifu
* WithGreatPowerComesGreatInsanity:
** The Atoniek armbands, which grant the human members of SG-1 super strength, speed and senses, also impair their judgement and decision-making skills. They never quite reach the full level of "insanity", but they begin to disobey orders ([[MilitaryMaverick well, more than usual]]) and recklessly use their powers, starting a BarBrawl and inadvertently hospitalizing SGC personnel.
** In "Absolute Power", Shifu, the Harcesis Child, gave Daniel a vision of what would happen if he gave Daniel the colletive knowledge of the Goa'uld. Daniel would become a despot who would murder millions of innocents and regularly fantasize about being a Goa'uld.
* WithinParameters: Justified. Sam notices that the power level of a force shield surrounding the town they are in (protecting it from the poisonous wasteland outside) is dropping. The other scientist present insists it is nothing. He is being brainwashed by the computer.
* WontTakeYesForAnAnswer: When the SGC was first founded and its members began to wonder what kind of institution it would become, Daniel pushed heavily for the anthropological study of the civilizations they encounter to be given just as much a priority as military development. He was so ready to do battle with the pig-headed, stubborn military minds of the base that Hammond could not get out the words to tell him that he agreed and would be following up with studies of the people they encountered.
* WoobieDestroyerOfWorlds:
** Played with in "Absolute Power" with Daniel Jackson. [[spoiler:In the episode, Daniel is trying to sensitively obtain information about the Goa'uld from the Harcesis, Shifu, who touches his head in an apparently hostile act, as it renders him unconscious. When he awakens, he proceeds to have all of the needed knowledge revealed to him and proceeds to build the weapon that would apparently defend the Earth, but at the cost of having become evil. He fantasizes about very violent things until, finally, his goal is met. He then proceeds to take over the most powerful weapon in the world from his SupervillainLair and destroy Moscow before waking up and realizing that having absolute power to defeat the Goa'uld in one fell swoop is not such a good idea after all. He wakes up to discover that it was AllJustADream, but during]] the episode, it was implied that WoobieDestroyerOfWorlds is actually simply a part of his subconscious, with or without special knowledge. Not surprising, really.
** [[RidiculouslyHumanRobot Reese, the scared, lonely robot girl]] who created the Replicators.
* TheWorfBarrage: In the episode "Beachhead", an Ori force-field is powered by the weapons fired at it.
* {{Workaholic}}: Carter has little to no life outside of the SGC, and spends her free time in her lab on the base running various experiments. In "Nemesis", she turns down O'Neill's offer to join him at his cabin for a fishing trip by saying that experimenting with new tech in her lab really is her idea of fun. When she is finally ''ordered'' to spend some time away from work in "Ascension", she comments that she really does not have anything else to do.
* WorldHealingWave: The original purpose of the Dakara Superweapon created by the Ancients, which restarted life in the Milky Way Galaxy after the Plague forced the Ancients to leave. As its current name suggests, no-one uses it for such benevolent purposes during the series.
* TheWorldIsAlwaysDoomed:
** First mentioned in "The Other Guys":
--->'''Felger:''' Don't worry, Colonel O'Neill, you can get back to saving the world for the sixth time.\\
'''Teal'c:''' Seventh.\\
'''O'Neill:''' You're counting?\\
'''Teal'c:''' ''[shrugs]''
** And then by Cameron Mitchell:
--->'''Mitchell:''' I think that was dealt with when you guys saved the world for the sixth or seventh time.\\
'''O'Neill:''' Ah, who's counting?\\
'''Mitchell:''' Teal'c, apparently. He mentions it quite a lot.
* WorldOfBadass
* WorldWarIII: The Goa'uld try to start one between the US and Russia in "Full Alert", but cooler heads prevail.
* WorthyOpponent: Arkad ''wants'' to be Teal'c's famed foe, and explains that he admired Teal'c's bravery and skill even when Teal'c killed his parents, but both Teal'c and Bra'tac have nothing but contempt for him.
* WritersCannotDoMath: Carter, of all people fall victim to this. In "Between Two Fires", the SGC gets an Ion Cannon to defend the planet against enemy ships in orbit. Carter calculates that they would need 38 cannons to cover all the planet's blind spots. While 38 would certainly get the job done, you can eliminate the blind spots on a sphere with as few as 4 (picture a tetrahedron).
* WrongGenreSavvy:
** In the GroundhogDayLoop episode "Window of Opportunity", Col. O'Neill remembers to record a conversation with Daniel as though it were mass amnesia rather than a space-time reset button.
** When the team is faced with a very real dragon, Col. Mitchell suddenly decides he is some kind of dracologist and plans to kill it by setting off a brick of C-4 underneath it, since "that's where dragons are weakest." The dragon proves him to be very wrong.

* XtremeKoolLetterz: Martin explains that the title "''Wormhole X-Treme!''" was a marketing decision, since shows with the letter "x" in their title do better than other shows.

* YearInsideHourOutside:
** This happens at the start of [[spoiler:"Unnatural Selection"]]; at the end it is [[SealedEvilInACan Year Outside Hour Inside.]]
** In the series finale, Sam does this to keep the ''Odyssey'' from getting blown to smithereens while she uses the extra time to try and figure a way out of danger. The good news is that she succeeds. The bad news is that [[spoiler:it takes her fifty years]].
* YeOldeButcheredeEnglishe: Averted. When SG-1 finds a tablet written in Middle English it is indecipherable to O'Neill and can only be identified ''as'' English by Daniel, the archaeologist.
* YesNoAnswerInterpretation:
** "Children of the Gods" provides the page quote. Jack answered Hammond's question about whether he could win against Apophis' Jaffa in a reasonably confident tone of voice, but by this point Air Force personnel have been torn up pretty badly by the Jaffa both times they've met them so you can understand Hammond not sharing Jack's confidence:
--->'''Hammond:''' Colonel, you've had the most experience in fighting this hostile. Assuming you have to defend yourself in the field, are you up to it?\\
'''Jack:''' We beat 'em once.\\
'''Hammond:''' I'll take that as a "maybe".
** After beaming onto an enemy ship and coming under heavy fire, Colonel Mitchell announces his presence and asks the enemy soldiers to surrender. When they don't stop shooting, he says "That's a no" and starts returning fire.
* YouAreInCommandNow:
** "Spirits" opens with O'Neill wounded by an arrow through the shoulder, forcing Carter to take command of SG-1 when they are sent through the gate to discover its source. O'Neill observes that it is her first command, commenting "cool."
** In "Lost City", General Hammond authorizes Carter to take command of SG-1 if she determines that the Ancient knowledge downloaded in O'Neill's mind is beginning to compromise his judgement. When she tells O'Neill of her orders, he says he understands and that she should take command ''now'' instead of waiting for him to lose control.
* YouAreNotReady: The standard explanation for why advanced alien races will not share their technology with Earth; the Asgard specifically explain that humanity is "too young." However, [[DeconstructedTrope unlike most examples of the trope]], the Asgard ''help humans get ready''. They gradually introduced the Tau'ri to their technology, first giving them devices and later showing how to manufacture this by themselves, so that they could appreciate their power and learn to handle them appropriately. This culminates with the dying Asgard race leaving humanity a matrix containing all their advanced technology.
* YouAreTheTranslatedForeignWord:
** Kasuf says in "Forever in a Day" that Sha're/Amonet's son is ''harcesis'', "the one who holds the secrets."
** In "A Hundred Days", Daniel explains that the "fire rain" is called a "falling star" on Earth, and Teal'c then gives the Goa'uld name of the phenomena. After a moment, Daniel translates that to "falling star".
* YouCantGoHomeAgain:
** Because of his MookFaceTurn in the pilot, Teal'c is unable to openly return to Chulak as long as Apophis rules there. Even after there is no longer an opposition to his return he remains on Earth, since he sees the Tau'ri as the best hope for overthrowing the Goa'uld.
** In "A Hundred Days", Jack is trapped offworld for three months because a meteorite buries the gate. [[spoiler:He's only able to return when the SGC manages to partially excavate it by firing a particle beam through it, then send Teal'c through to dig the rest of the way to the surface.]]
** Jonas Quinn spent season six living on Earth and unable to return to his home, the nation Kelowna on the planet Langara, because he stole a quantity of naquadriah to give to the SGC.
* YouDidntAsk: In "Brief Candle" Daniel encounters Linear-A script, which has never been fully deciphered on Earth, but Teal'c recognizes it as an old dialect of Goa'uld. When he is able to read part of the script, Daniel asks why he did not mention it before, and Teal'c responds that Daniel "did not inquire."
* YouDONOTWantToKnow: In "Space Race", while acting as a co-pilot in an Alien Grande Prix, Samantha Carter hears some alien trash talk. Her pilot tells a competitor to "Eat Greeven!" When she asks what 'Greeven' is, he tells her "Don't ask."
* YouHadUsWorriedThere: O'Neill jumping an about-to-explode Stargate away from the Earth, with a scare about whether or not he was able to eject.
* YouHaveGotToBeKiddingMe: Practically O'Neill's catch phrase.
* YouHaveFailedMe: Standard Goa'uld operating procedure.
* YouLookFamiliar:
** Mitchell Kosterman first appears in "Seth" as ATF Special Agent James Hamner, then again in "Heroes" as Colonel Tom Rundell.
** Dion Johnstone played a total of ''seven'' roles over the course of the show, often under heavy makeup. He played (in order): Captain Nelson in "Rules of Engagement", Na'onak in "Jolinar's Memory" and "The Devil You Know" (before his mask was removed [[TheOtherDarrin and a new actor took over]]), an unnamed alien in "Foothold" (identified as "Alien #2"), Chaka in "The First Ones" and "Beast of Burden", Lieutenant Tyler in "The Fifth Man", Wodan in "Metamorphosis" and Captain Warrick Finn in "Forsaken".[[invoked]]
** David Palffy portrayed the Goa'uld Sokar in season three and returned as the robe-shrouded incorporeal form of Anubis from the end of season five up to "Lost City". He continued to voice Anubis through season 8, with the exception of [[spoiler:Anubis's ascended form in the diner between worlds]].
** Patrick Currie played three separate roles, but never actually looked the same in any of them: Two of his three roles were in heavy makeup as aliens. He was Chaka in "Enemy Mine", Eamon in "Space Race" and the Replicator Fifth in multiple episodes in seasons six and eight.
** Anne Marie [=DeLuise=] played Farrel in "The Other Side" and returned as Amy Vanderburg in "Bounty".
** David Lovgren first appeared as Va'lar in the episode "Threshold", reappearing as Darrell Grimes in "Bounty".
** Mike Dopud plays Russian Air Force Col. Ruslan Chernoshev in "Full Alert" and BountyHunter Odai Ventrell in "Bounty". He then reappears as Lucian Alliance member Varro in ''Series/StargateUniverse''.
** Peter Bryant played Teal'c's old friend Fro'tak in "Family", then rogue NID agent Hoskins in "Affinity" and "Endgame".
** Alessandro Juliani played Eliam in "Scorched Earth" and Katep in "Moebius Part 1 & 2"
* YouMeddlingKids: Daniel says the line at the end of "Bounty".
* YoungerThanTheyLook: The people of "Brief Candle" are all being artificially aged by Goa'uld technology at a rate of approximately one year per day. When he discovers this, O'Neill is rather disturbed to learn that the woman he slept with was not thirty years old, but thirty ''days'' old.
* YourApprovalFillsMeWithShame: In "Beachhead", everyone is understandably perturbed when minor Goa'uld Nerus attempt to butter them up by congratulating them for their role in ending the reign of the System Lords.
* YourCostumeNeedsWork: When O'Neill is on the set of ''[[ShowWithinAShow Wormhole X-Treme!]]'' he goes to the security office to get information on recent visitors to the studio. He is first told how to find the auditions, and then needs to add "really" after he explains that he is from the actual Air Force.
* YouRemindMeOfX: Teal'c once says that Mitchell reminds him heavily of O'Neill, which Mitchell takes as a compliment. [[StealthInsult Teal'c says that it is up to him]].
* [[YoureNotMyFather You're Not My Mother]]: Cassandra says it to her adoptive mother, Dr. Fraiser, in "Rite of Passage". To be fair, the teenager is quite feverish and stressed from the effects of Nirrti's retrovirus at the time.
* YourMom: In the fifth season episode "Failsafe", O'Neill and Jackson recount how a particular negotiation with the Asgard went south.
-->'''O'Neill:''' ... And after that, I kind of lost my temper.\\
'''Hammond:''' What exactly does ''that'' mean?\\
'''Jackson:''' Let's just say Jack made a reference to Freyr's mother.

* ZombieApocalypse: Mitchell's pitch for a story idea in "200" is that the Telchak device ([[ContinuityNod Previously seen in "Evolution"]]) is causing zombies to arise in the SGC. He is forced to [[GunsAkimbo battle them with two SMGs]].