Leela: You're blackmailing me?
Bender: 'Blackmail' is such an ugly word. I prefer 'extortion'. The 'X' makes it sound cool.There's always something about the letter X that just makes anything cool (including this article). A lot of people use it gratuitously on a name, product, model, etc. just so it has some sort of edge to it. Want some pizzazz? Add an X somewhere in the name. It doesn't matter where, as long as there's an X. And it has to be a capital X. Lowercase x is just too puny to be cool. Just don't add 3. In order for this trope to work, though:
— Futurama, "Anthology of Interest I"
- The product isn't the 10th installment of a series that already used Roman numerals.
- On the other hand, if the series goes 1, 2, 3, 4, 5, 6, 7, 8, 9, X...
- The X doesn't stand for a multiple of something. Example would be AMD's line of processors: Athlon X2, Phenom X3, Phenom X4, etc. (They denote how many cores there are.)
- There's no real justification to use the X. Another letter would easily work if the X was a part of a word.
- If it's in the designation of a vehicle or other object, it can't be a prototype. In such cases it stands for experimental, and gets changed or removed when it enters full production.
- Though it does add that extra bit of coolness to a Super Prototype, we admit.
- Similar to the above, the X in question is used as an abbreviation in an acronym for a word in English that has the ex- prefix, which would properly use E, but X looks cooler, of course. (Only a few English words begin with X, and most of those derive from Greek. The same holds for most European languages.)
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Anime and Manga
- Speed Racer has Racer X. And later named a child "X".
- Sonic X, but we all know that Sonic is cool anyway.
- X1999, an anime made by CLAMP. Then they went overboard and became ×××HOLiC... (The xxx is silent, it denotes a variable in Japanese. The English would be ___holic.)
- The working title for Pokémon 2000 movie was Pokémon X, and in fact there is a faint X shape in the final version poster/cover of the Japanese version.
- That explains why Lugia is referred to as 'Mystery Pokémon X' in a Johto miniarc.
- Gundam X, though it didn't quite work...
- Justified, though, in that the titular Gundam's wing binders open up in the shape of an X when it deploys its Satellite Cannon.
- Turn A Gundam gives us the Turn-X Gundam. Whose name doesn't make a lick of sense, but the thing is awesome and deadly!
- The Lyrical Nanoha franchise gave us Striker S Sound Stage X. Confused some people into thinking that this was the tenth Sound Stage (it was the eleventh, excluding the Megami Sound Stages). The X stood for the Mysterious Waif.
- The titular character from B't X is a mechanical kirin, famous for being the most powerful battler of the villainous Machine Empire. Fortunately, he decides to help the hero...
- While they haven't yet appeared in the show, the Yu-Gi-Oh! card game has the X-Sabers and their beefed-up cousins, the XX-Sabers. I hate to see what they do with the third installment of the monster series.
- Also the most probable reason for 4Kids deciding to pronounce the previously silent X in Yu-Gi-Oh! ZEXAL
- Cannon God Exaxxion has not one, but three Xs. They explain later that the XXX marks that are stamped all over the title robot aren't really Xs at all, but rather the last letter of the alphabet used by the aliens who created it. XXX is their generic symbol for an antimatter reactor, as the letter has similar connotations to the Greek letter Omega.
- Planet X in Transformers Cybertron.
- The Girls Love manga Hayate × Blade (where the X is pronounced "cross".)
- Bleach deals with an organization called Xcution.
- Lille Barro of the Vandenreich has an ability called "The X-Axis", one of the most powerful abilities seen among the Schrift and outside of it, and he is an expert sniper with heavy angel motifs.
- Romeo X Juliet, where the X is still intended to be pronounced "and".
- This is the basis behind the name of X-Brawn in Transformers: Robots in Disguise. It was for a whole thought that X-Brawn was used because Hasbro couldn't secure a trademark on 'Brawn', but one of their marketers later explained that they just put in the X too look cool.
- Mysterious Girlfriend X. Extra-strange because the X doesn't seem to mean anything (the "mysterious girlfriend" has an actual name).
- The anime adaptation of Rurouni Kenshin has two english dubs. One of them leaves the title unchanged, while the other renames the show "Samurai X".
- X-Men. Because ex-men just doesn't sound cool enough.
- But for some reason, Ex-Mutants was...or maybe not.
- Stan Lee wanted to call it "The Mutants," but Executive Meddling (this was The '60s, he wasn't an executive yet) prevailed. He was told that nobody would know what a mutant was. "But they would know what an "X-Man" is?" fell on deaf ears.
- X-Men spinoffs have driven this so far into the ground it's punched right through the planet.
- X-Treme X-Men being the ultimate offender.
- Not to mention peripheral X-character "Adam X the X-Treme." Created in the heyday of the Nineties Anti-Hero, he has that name and the power to ignite people's blood and possesses more spikes than actual bad guys in order to expose said blood to the air. Basically the living definition of "trying too hard." (Last seen setting The Juggernaut on fire, and then realizing that he'd set the Juggernaut on fire. Yeah, that coulda gone better.)
- Wolverine has a villain called Mister X.
- Moira MacTaggert's prisoner, the mysterious Mutant X, who turned out to be her son, AKA Proteus. The name was dusted off in the '90s for the comic book starring Havok trapped in a Parallel Universe, and an unrelated TV series Marvel had some hand in (Alphas is sort of a Spiritual Successor).
- The Guardians of the Galaxy's Groot comes from Planet X. He was invented in Marvel's 1950's monster comics, where the name "Planet X" was actually recycled a few times, but the name seems to have stuck in his case.
- Comic artist Frank Granados goes as "Franx Granados" (or just "Franx").
- Harry Potter Fanfic My Immortal features goffik band XBlakXTearX, featuring Serious Blak, Snap, Lucian Malfoy, and Jamez "Samoro" Potter. Notable for the fact that the latter once shot Lucan's arm off for playing a song wrong.
- Paper Mario X. The X stands for crossover.
- One of the most popular Super Mario Bros. fangames has the title Super Mario Bros X. After the original URL where the game was located, supermariobros.org, was purchased by Nintendo, the creators were able to get away with it by adding an X to it (supermariobrosx.org), also invoking this trope.
- The former MPAA rating X, now essentially synonymous with pornography.
- "XXX", a porn industry marketing gimmick intended to imply something along the lines of "this movie is three times raunchier than an ordinary X".
- And the less-desirable XX.
- xXx, starring Vin Diesel. xXx's real name is Xander Cage, so the xXx tattooed on his neck could be his initial repeated three times. However, after he steals an anti-game senator's sports car and drives it off a bridge so he can BASE jump off it in the opening scenes, Samuel L. Jackson's character suggests the three X's could also mean three "strikes" against the law.
- X-Wings in Star Wars are, like other crafts of the Rebel Alliance, named so because they look like that letter. This is interesting because the Star Wars universe uses the Aurebesh script, leading to the question why inhabitants of a galaxy "far, far away" should name their ships after Latin letters. Translation Convention, or just more Inexplicable Cultural Ties? Eventually it's retconned that a "High Galactic" script that's inexplicably identical to the Latin alphabet also exists in the Star Wars universe.
- The League of Extraordinary Gentlemen Film of the Book is acronymed LXG. Why? Just because.
- Advertisements for Malcolm X often featured simply a lone "X" logo. This actually backfired a bit on them because you cannot trademark a letter, so the filmmakers could not claim a cut from knock-off merchandise.
- The spacecraft Zero-X in the first Thunderbirds film, Thunderbirds Are GO. Not a prototype, this was the one intended for the first trip to Mars, until it failed during liftoff and exploded in the ocean. The replacement ship that launched two years later (2067) was also called Zero-X.
- In the backstory of Captain Scarlet and the Mysterons, a third Zero-X mission was launched in 2068 (the second Zero-X also exploded), suggesting that the name refers to the spacecraft design, as well as with the only extant ship.
- Jason X, which also just happened to be the tenth movie in the Friday the 13th series.
- In the remake of The Longest Yard, Joey Battle (played by Bill Goldberg) has "X" as his uniform "number".
- Agnes Nitt, a young woman in the Discworld novels, desperately tries to acquire some cool by (briefly) assuming the name Perdita X Dream, where "X" stands for "someone who has a cool and exciting middle name." Doesn't work though — all the people in her village refer to her as "the Agnes who calls herself Perditax."
- In Unseen Academicals, we find that Dr. Hicks, the head of Post-Mortem Communications at Unseen University first introduced in Making Money, has started spelling his last name Hix because "a man who wears a black robe with nasty symbols on it and has a skull ring would be mad, or let us say even madder, to pass up the chance to have an X in his name."
- Discworld also features the continent XXXX; this was originally a mapmaker's label, as in it was so unknown they didn't even know what a good name was for it. "Fourecks" actually became its name.
- XXXX is also the name of a well known Australian beer, pronounced Fourecks.
- In Craig Charles' The Log, he advises any heroes in a movie, when confronted with the villain's office full of filing cabinets, to go straight for the one labelled 'X'. "No evil mastermind has ever named his plan to Take Over the World 'Project W', guys."
- The Echthroi in Madeleine L'Engle's book A Wind in the Door have the power to unmake elements of creation, a process referred to as Xing.
- Daniel X
- In The Pendragon Adventure, the biggest competition in Quillain's existence is the Grand X.
- The SF trilogy by Ramez Naam: "Nexus", "Crux", "Apex". The second one even got a somewhat shoehorned Title Drop in the respective book, as if to say: "Hey, it's totally NOT this trope!"
Live Action TV
- The TV show Wormhole X-Treme! within Stargate SG-1.
Martin: Research says that shows with "X" in the name get higher ratings.
- Starfleet designates experimental starships' line number with NX, instead of the usual NCC. Unfortunately, NX is changed to NCC as soon as the model enters common use.
- In Star Trek: Enterprise, the "NX" designation is used for the entire class of starships that the Enerprise belongs to, as the Earth Starfleet operates under different conventions than the chronologically later series' Federation Starfleet.
- Every proper noun in the language of Neelix's species, the Talaxians, contains an X somewhere.
- In Kaizoku Sentai Gokaiger, the Transformation Sequence includes three Xs (and a V) because Gokaiger is the 35th Super Sentai series.
- Disney XD, or "eXtremely Digital". That's right, little boys, Disney is cool now and totally not just for girls.
- Most Extreme Elimination Challenge or just MXC. Don't get eliminated!
- The X-Files:
- The famous FBI department is called simply X-Files for no apparent reason. However, there is a really cool explanation which appeared on the show in season 5. They might have been called the U-Files for "unsolved" but weren't thanks to the filing system at the FBI in the 50's.
Clerk Bahnsen: It's in an X-file.Agent Dales: An "X-file"?Clerk Bahnsen: Yes, unsolved cases. I file them under "X".Agent Dales: Why don't you file them under "U" for "unsolved"?Clerk Bahnsen: That's what I did until I ran out of room. Plenty of room in the "X"s.
- Agent Mulder's second Mysterious Informant is known only as Mr. X.
- The famous FBI department is called simply X-Files for no apparent reason. However, there is a really cool explanation which appeared on the show in season 5. They might have been called the U-Files for "unsolved" but weren't thanks to the filing system at the FBI in the 50's.
- Kamen Riders X, ZX, and Black RX.
- Ultraman X puts the X on whatever it can find. Heck, the Xio team Home Base is a giant building shaped like an X!
- X Japan was originally just named just X. They changed their name when they gained international recognition because there was already a punk band in the USA called X.
- In the opposite direction, for a few years in the 1990s British band Bush was known as Bush X in Canada, because a Canadian band from the 1970s still owned the name there.
- British group Liberty X added their X for similar reasons, after being formed from a TV talent show's runners-up as plain 'Liberty'. This was a permanent change, though, as the name was contested within the UK, rather than being a monicker-of-convenience temporarily adopted abroad.
- Progressive metal group Symphony X.
- Brand X.
- Rapper and sometimes Riddick-antagonist Xzibit.
- Don't overlook his signature song that goes "X! (untz-untz-untzuntz) X! (untz-cont'd)"
- The band The xx
- Hardcore Punk and Metallic Hardcore bands (particularly those of the Straight Edge persuasion): X's drawn or tattooed on hands are common fashion and often incorporated into band names as well (examples include xDeathstarx, xTyrantx and xLooking Forwardx).
- The ur-example is Los Angeles punk band X, led by John Doe and Exene Cervenka.
- And the Australian band with the same name.
- Gibson Guitar Corporation created the mixedly-received Firebird X, an electric guitar with digital effects and other futuristic additions. Granted, the previous Firebird models are defined with roman numerals (Firebird I, II, III, V, VII and XII) but there never was a VI, VIII or IX. Neither was there XI making the XII and X most probably this trope..
- Industrial and EBM bands are fond of this trope. We have X-RX, X-Fusion (and Noisuf-X), Studio-X, XP8, H.E.X.E., among others. Even bands that don't strictly fit this trope still make frequent use of Xtreme Kool Letterz.
- Borderline case: Charlie Sexton's 2nd album, titled just "Charlie Sexton", with the "X" of his name red and x-tra large. Hey, theoretically he could have used any other letter than the X for that purpose, so it falls under this trope...
- XTC. Doubles, of course, as a Pun on ecstasy.
- Progressive rock band Twelfth Night's 1986 album is sometimes listed as X, but that's actually a mistake. The cover features the band's name incorporated into what looks like a double-underlined X, but is actually the Roman numeral XII (for Twelfth) on its side. The album's actually called Twelfth Night.
- The seventeenth and eighteenth WrestleManias, called, respectively, WrestleMania X-Seven and WrestleMania X8.
- Then there was "X-Pac," though it wasn't clear what his name was supposed to mean.
- And short-lived, MTV-backed promotion Wrestling Society X.
- D-Generation X
- TNA's X-Division, the Ultimate X match, and the pay per view Destination X.
- No better way to exemplify the trope than Vince Russo's early TNA stable "Sports Entertainment Xtreme"note
- The Xbox line of game consoles is the highest profile example in all of video gaming. Although its ancestor, the 8-bit MSX computer line, invoked this trope all the way back in the 1980s.
- Mega Man X. This may have caused confusion, as the American release used Roman Numerals to denote the title while Japan used Arabic numbers. So to Japan, Mega Man X was just a name. To Americans, they might have thought this was the tenth Mega Man game (though this was Jossed long before the release of Mega Man 10).
- X-Blades, for no real reason.
- Originally called Oniblade, which would make this a case of Anime Makes Anything Cool.
- Dance Dance Revolution recently joined in the group of games with an X: Dance Dance Revolution X. Although there is some meaning to it as it was released during the game's tenth anniversary.
- Metal Slug X and Metal Slug XX, which were remakes of Metal Slug 2 and Metal Slug 7.
- Microsoft Flight Simulator X, the tenth game in the series. All previous Flight Simulator games were named after the year they were released.
- Super Smash Bros Brawl is titled Dairantou! Smash Bros X in Japan. Melee was also DX, short for DeluXe.
- Thanks to the 4-character limit in Final Fantasy I on the NES, X-Zone was named XXXX. X-Zone also appears in Final Fantasy VI.
- On the subject of the Final Fantasy series, Final Fantasy X-2 probably counts as an aversion, as the X still stands for "ten", the game that X-2 is a direct sequel to. Yes, this means there are two layers of numbering on this game; what's your point?
- Guilty Gear X and XX.
- Paper Mario: The Thousand-Year Door has the X-Nauts.
- And the X-Yux (supposedly pronounced "cross-yux"). Or just the Yux in general.
- Pokemon XD, even if it is a Meaningful Name.
- In Metroid Fusion, the alien baddies were named 'X'. These were so Badass, the old ones had to create a bioweapon to stop it, which was then stolen and used to terrorize the galaxy.
- 4X strategy games. They should actually be Four E strategy games, but X is cooler.
- Every member of the Organization XIII in the Kingdom Hearts series have an X in their names in a form of Theme Naming — their names are an anagram of their original name, plus an X. Some of these work fairly well like Dilan becoming Xaldin, but some like Axel just seemed to raise questions and eyebrows. Even when his real name was revealed to be the slightly feminine looking Lea (pronounced Lee to mitigate that) in 358/2 Days. The exception is Xemnas, who stole the name Ansem before his transformation. His original self was named Xehanort, which, if the X is removed, can make "no heart" and "another"
- There's also the χ-blade from Kingdom Hearts: Birth by Sleep. It's spelled like the actual Greek letter "khi"(or chi), which makes it a Multiple Reference Pun and is the reason for the Organization's naming practices mentioned above. And it's wielder can fire a Sword Beam, of course in the shape of an X.
- The Japan-only Game Boy game X and its DSiWare sequel X-Scape
- The DSiWare game Photo Dojo, known as Photo Fighter X in Japan.
- In Xenosaga, the character KOS-MOS (she's a robot...imagine that) has a development code of KP-X.
- The Japanese version of Super Street Fighter II Turbo is called Super Street Fighter II X (likely changed due to the fact that the letter X could be confused with the roman numeral for ten). This is the reason why the letter "X" appears when a Super Combo is used in the Game Boy Advance version, as well as why the "Super Turbo"-like fighting style in Street Fighter Alpha 3 is called "X-ism".
- Command & Conquer: The First Decade has an X superimposed in the box art. Of course, it makes sense, but you know....
- Early 90s arcade shooter Xexex, which also has the benefit of being a palindrome.
- The final boss music from Touhou Hisoutensoku is Unknown X, Unfound Adventure.
- When Phoenix Wright gets a cold, his favorite brand of cold medicine is called Cold Killer X. Note, this only applies to the localization. In the original Japanese version, it was called Cold Killer Z.
- Daniel Remar likes to use the Roman "X" instead of "10" in his games (such as Iji) for this reason.
- The Sega Genesis CDX was an all-in-one console that could play both cartridge and CD games, and also served as a (not very) portable audio CD player. The Genesis also had the 32X add-on.
- The early online adapter for the Genesis and the SNES, the XBAND.
- In the mid-90s, a reader of Electronic Gaming Monthly who noticed this phenomenon wrote a letter to the editors asking what the deal was. EGM responded with a sarcastic, dismissive remark, because at the time, EGM responded to every letter with a sarcastic, dismissive remark.
- Before its release, the code name of the first PlayStation was PS-X, short for PlayStation-eXperimental. Later, Sony released a digital video recorder with integrated Playstation and PlayStation 2 hardware, called PSX.
- The PSX...err, PS1 games 1Xtreme, 2Xtreme, and 3Xtreme. Supposedly they are a combination of racing and eXtreme sports, as in rollerblades and skateboards.
- Playboy X
- X-Com. It stands for "eXtraterrestial COMbat unit". And sounds extremely cool.
- Egosoft's X-Universe, an entire series which gets its name from the player's ship in X: Beyond the Frontier: The Xperimental Shuttle.
- The tenth Mortal Kombat game is called "Mortal Kombat X" (which is "ex" as in "next"...but also "10").
- The sequel to Xenoblade is entitled Xenoblade X. No explanation has yet been given for the X in the title, though until recently the codename for the game was just "X" before it was revealed to be a Xenoblade sequel.
- Klaxxon, so cool they x-ed it twice. (If not it wouldn't have been an example. In this case, the X is somewhat justified - can you imagine the game being titled "Horn" or "Siren"? - because you get extra points for making a big X in gameplay.)
- xkcd. According to Word of God, it doesn't stand for anything, it's chosen to make it difficult to pronounce, and of course because it's cool. And yes, it's official spelling is with all lowercase, or possibly all uppercase if that is not usable for some reason. Xkcd is frowned upon.
- Well, Xykon from The Order of the Stick certainly thinks so. He chose the name Xykon for himself after meeting a man named Xavion who wanted to recruit him for his team of sorcerers, and thought the name "Xavion" sounded cool.
- A certain very NSFW site URL begins with ex- (no triple x though) and directly cites the above Futurama quote. It's hit #45389 from 82600 if you ''have'' to google.
- This trope is discussed during The Runaway Guys' Let's Play of Mario Party 4:
- The YouTube 10 year Milestone Celebration video is an "A-to-Z". The word "experiments" is used for the X.
- Protoform X in Beast Wars.
- Along with Cheetor's line that the pod was branded with "a big, bad-lookin' X!"
- Planet X in the Duck Dodgers cartoons.
- The Powerpuff Girls were brought to life and given their ultra-super powers via Chemical X. In one episode Mojo Jojo removes their powers using Antidote X.
- Teen Titans features a villain named Red X. Although he does utilise a variety of tools with an "X" motif, the design of the tools would entirely depend on the user's taste, so the trope still applies.
- "X Agent" from Sheep in the Big City. The trope was parodied in his first appearance:
General Specific: I don't want an "X Agent"! I want a current agent!
Private Public: The "X" is put in to indicate mysteriousness rather than his job status sir.
General Specific: Well why can't he choose another letter? Like "K"?
Private Public: "K" isn't as mysterious a letter as "X", sir.
General Specific: What about "L"? "L" is pretty mysterious! [waving fingers] Llllllllllllll...Lllllllll!!!
Narrator: So, as General Specific re-acquaints himself with the alphabet...
- Johnny Test has Johnny X.
- Dimension X from Teenage Mutant Ninja Turtles (1987), which is alternately described as a distant spiral galaxy or an alternate dimension.
- The operating system UNIX. Originally it was Unics, a pun on "Multics".
- The X Window System for UNIX and Linux (which includes x-terminal, x-clock, etc). Justified—it's predecessor was "W", as in windowing.
- Microsoft seems to like this trope.
- Back in the '80's, they made a version of Unixnote which they called Xenix.
- Windows XP. The XP stands for eXPerience, possibly because someone at Microsoft Central had been playing Dungeons & Dragons.
- Microsoft's "DirectX" and "ActiveX" APIs. What does the X convey about the product, exactly? actual answer
- The Xbox falls under this trope as well. Microsoft realized that "DirectX Box" just didn't sound all that catchy. The Xbox is, essentially, just a computer with streamlined DirectX support, one of the reasons why it and its successor are touted as being "developer friendly."
- XML (eXtensible Markup Language) and related standards, such as XHTML, XSL (including XSLT and XSL-FO), XForms, XPath, XQuery, XLink, XPointer, and so on.
- On a side note, there's actually an older, unrelated XForms(a GUI toolkit), which is completely justified since it was ported from IrisGL to X11.
- Of course, hardware names can't be avoided either:
- The XT, ATX, BTX, and DTX motherboard design standards. The X supposedly means eXtended.
- The PCI slot had an upgraded cousin, the PCI-X slot (again, meaning eXtended).
- When PCI-Express came about, people thought PCI-X meant that. PCI-Express's unofficial bbreviation is PCIe.
- ATI/AMD and NVIDIA all have an X card, even though ATI/AMD stopped this moniker a while ago. For NVIDIA, the X moniker means it's the high end card, usually marketed to gamers.
- The graphics card company XFX, which also slaps on XXX when one X isn't enough for their souped up graphics cards. So you end up with cards like the "XFX GeForce 9800 GTX XXX edition."
- Intel uses XE for the "Extreme Edition" processors (it was formerly EE) and, with their part numbers sporting an X. Any high-end chipset also sports an X.
- Intel also has the Xeon line of processors.
- AMD is guilty of the X moniker. Their old lineup of high performance processors was the FX series. Their chipsets also have an X at the end for the high end models.
- Corsair has its XMS brand of memory.
- The codenames for the Xbox 360's processor and GPU are the Xenon and Xenos, respectively. The PlayStation 3's GPU is the RSX.
- Creative Lab's X-Fi, for eXtreme Fidelity!
- And some actual computer models:
- Dell's eXtreme Performance System, or XPS. EPS wouldn't be a great marketing name, would it? They also pretty much tacked it on to every computer they have
- IBM PC-XT.
- Gateway's high end laptops: FX.
- Alienware has the M1#X and the ALX series of computers.
- Pixel, which stands for picture elements. Which one is koolernote : 1280x768 picel, or 1280x768 pixel?
- ESX stands for Elastic Sky, apparently. (V Mware server virtualization product.)
- Products that for some reason go from version "9" into version "X". Roman numerals + Xtreme Kool Letterz = Rule of Cool.
- Mac OS X. All previous versions were numbered using Arabic numbers.
- The new version of QuickTime included with OS X Snow Leopard is so Xtreme that it skipped from version 7 to version X.
- The ATi X series of video chipsets, which came after the 9000 series.
- Paint Shop Pro, made by Jasc and then bought by Corel, originally used 1-8 for its version numbers. When Corel bought it, it went from 8 to IX. Then came X, then XI. As the switch happened with 9, not 10, one might be inclined to think this might not be a case of Xtreme Kool Letterz... until the 12th version came out as "X2".
- Partly from superstition about the number 13, and partly so they could have cool letter in its name, the thirteenth version of Wordperfect Office is called X3. (And who is this WP Office owned by? Do we see a pattern here?)
- Adobe in early 2011, released their tenth version of their PDF reader. They also invoked this trope by calling it Adobe Reader X.
- Adobe then went on to release version eleven as Adobe Reader XI.
- The X.500 cryptography standards. Supposedly this is shorthand for Public Key Infrastructure, which is shortened to PKIX.
- Various car manufacturers attach an X somewhere in their car names.
- The hatchback versions of the Honda Civic have an X attached at the end. DX and RX are their most common models.
- Mazda's line of sports cars sport an X such as the Miata (MX-5) and the RX-7 and RX-8.
- Ford has an XLT version of its F-150 line of trucks.
- And for years Ford had a compact car called a "ZX_", peaking in 2005-06 when every USDM Focus model had such a designation (ZX3-3 door hatchback, ZX5-5 door hatchback, ZX4-sedan, ZXW-wagon).
- Acura's compact hot-hatch is the RSX. Its three SUV models are the MDX, the RDX, and the ZDX. Its new entry level sedan is the ILX. And of course its sports car was the NSX. A new NSX model is coming around 2015.
- The NSX is also a case of Let X Be the Unknown.
- Nissan's Fairlady Z 300ZX, and 180SX/240SX (depends on where do you live).
- Subaru Impreza WRX
- Vespa mostly uses this straight, but inverts it in the LX series; The series was launched in 60th anniversary of the (Italian) company, and LX is Roman numerals for 60.
- Julius Caesar's most trusted elite unit was the 10th legion, which in Latin had the full name Legio X Equestris. His successor Augustus later created the Legio X Fretensis after Caesar's famous legion, making this trope Older Than Feudalism. Both legions happened to become famous in history. The Equestris was one of the most important units in the conquest of Gaul. In the Year of Four Emperors, the commander of the Fretensis, which happened to fight a massive uprising in Judaea at the time, split his forces and put an end to the power struggle in Rome and became Emperor Vespasian, while at the same time his son Titus continued to fight the Jewish rebels. Titus led the still famous Siege of Masada and became the first son of an Emperor who succeeded his father to the throne. Later the legion was part of the army led by Trajan against the Persians, who also happened to become emperor.
- Italian fascist government followed the Roman example by naming its elite naval commando unit X MAS (or 10th assault flotilla). They performed a number of daring missions against the Royal Navy in the Mediterranean, especially using saboteur divers (including the mining of battleships Valiant and Queen Elizabeth, which left the British Mediterranean Fleet without a battleship for about a full year).
- The U.S. military enjoys putting X in front of every eXperimental weapon name, along with the usual M. The XM16E, XM29, XM25, and XM8 are some recent examples (well not the XM16E).
- Out of all the letters in the alphabet to choose for the default variable in anything, why does "x" have to be it?
- X-rays: Because "Röentgen rays" just doesn't have the right sound to it. (Reportedly, Prof. Wilhelm Röntgen actually preferred the term "X" over his own name, despite the fact that he was was the one that discovered them.)
- Tokyo X, a breed of pig that is known for its quality meat...or a Japanese rock band.)
- The EX-F1, an amateur-made rail gun.
- The short lived XFL, a particularly good example in that unlike some of the others, the X didn't stand for eXtreme—it was just an X.
- Malcolm Little, who became Malcolm X based on the practice of Nation of Islam converts rejecting their "slave names" and replacing their surnames with X until they earned a new name through a pilgrimage.
- David X. Cohen, a writer for Futurama. When he joined the Writer's Guild, he found his birth name, David S. Cohen, had already been taken, and the Guild has a strict "No Duplicate Names" rule for various legal reasons, so he chose the middle initial X because it sounded sci-fi. If asked what X stands for, he'll often say it just stands for X.
- Many people named Francis X., including the original Francis X. himself, St. Francis Xavier.
- Planet X, the name of a hypothetical planet in the far outer solar system. Not only sounded cool, but had the "X the unknown" thing and would also have been the 10th planet, this being before the discovery of the Kuiper belt and that business with Pluto.note
- Dubai Airport is written as DXB in all shortened forms such as on plane tickets and on arrivals timings.
- LAX, i.e. Los Angeles?
- Practically any time a word starting with "ex-" is shortened for an acronym, the letter X is used, instead of E. This has been particularly true for the word "extreme", which is so often shortened to "X-treme" that many usages don't need to explain themselves, such as the the X Games.
- "Christmas" is often abbreviated as "Xmas" in writing, as the Greek letter Chi, which looks like X, is the first letter of Xristos (Χρἰστος), Greek for "Christ". The "Chi-Rho", which looks like an "XP" in the Latin alphabet and usually written one on top of the other, was an ancient symbol for Christ- "chi rho" ("ch" "r") being the two first Greek letters of the word "Christ".
- Exxon. It doesn't mean anything, it doesn't stand for anythingnote , it was chosen because it was a) distinctive, b) not already trademarked, and c) sounded cool.
- JAXA: the Japan Aerospace eXploration Agency. Sounds a lot better than JAEA, doesn't it? And it doesn't hurt that it rhymes with NASA.
- On the stock market front, the Toronto Stock Exchange recently changed its initials from TSE to TSX for this simple reason.
- A giant, 40-foot Pliosaurus found in Svalbard was nicknamed "Predator X" until its formal description was released.
- A Norwegian 6-year old forced his parents to deliver a letter he wrote to the King of Norway, asking for permission to change his name to Sonic X.
- The name Robert X. Cringely, well-known in tech circles, was entirely made up by InfoWorld magazine to provide some continuity for one of their columns, which would otherwise have been attributed to a string of short-lived writers. However, one Mark Stephens picked up the column and gained much fame with the Cringely name in the '90s. InfoWorld fired Stephens in 1995 and still has other writers filling in as "Cringely," but let him use the name outside of competing magazines as a settlement.
- Brazilian entrepreneur Eike Batista names all of his companies '**X' (EBX, MMX, OGX, MPX, LLX...), because he wants to "multiply wealth".
- Axe Body Spray. They wanted a different name for its UK distribution, so they went with "Lynx," presumably by the time-honored method of "Are there any other short, manly-sounding words with X in them?"
- Sometimes, expressway name abbreviations are written in this way. One example is in Baltimore, where Interstate 83 terminates as the "Jones Falls Expressway" (JFX).
- ArXiv, the preprint server. (Formerly xxx.lanl.gov, a joke to get the site blocked. After the total success the joke became a bit counterproductive.)