Also there's Pantyhose Taro. Bathed in a Jusenkyo spring at birth where a yeti holding an eel and crane while riding an ox drowned. Later he bathes in a spring where an octopus drowned.* "Drowned" meaning "dunked and sinking" as shown in the Phoenix People arc.
In Ah! My Goddess, the demon leader Hild has a creature that eats angels, which are effectively the goddess' souls. It is a gigantic, powerful leviathan. And she named it "Kittens".
In an episode of Ninin Ga Shinobuden, Shinobu names her giant, mobile, carnivorous plant monster Pochinosuke ("Pochi" being the Japanese equivalent of "Rover" or "Fido" and "nosuke" being an archaic boys' name ending). She's the only one who can keep it from wreaking havoc.
A recurring villain in Kinnikuman is one of the biggest chojin in the series, a living mass of sand who sadistically brutalizes his opponents. He was responsible for Prince Kamehame's death during the Dream Tag Tournament arc. His name? Sunshine. (He's named after the Sunshine Towers of Peru). There are some other dangerous villains with silly names, but at least they have the decency to look silly, too.
In Baccano!, America's craziest and most terrifying assassin has the misfortune of being named Claire which, while not incapable of being attached tototal badasses, doesn't exactly work that way when the badass in particular is male. Fans like to joke that this is the reason he keeps on making up new names. Also a bit of Have a Gay Old Time since prior to the 50s, Claire was a man's name. In 1930, his name would have been normal - the twist only comes for modern viewers who are used to it being a female name, although even in 1930, it was more common for women than for men in this particular spelling.
Out of omniscience-boredom, a reality-warping Eldritch Abomination decided to take human form and join the ranks of the Martillo family camorra. It's name is Ronnie.
Durarara!! has Celty's headless demon horse. His name is Shooter.
Triela of Gunslinger Girl, was given the nickname "Lepretto" (roughly "bunny" or "little hare") by the GIS Special Forces guys she trained with, after a child's doll that shares her Girlish Pigtails. When they meet up again on a later mission, a couple of the GIS guys rub her hair and comment how "rubbing a rabbit's foot before mission will bring you good luck". They need the luck, they're going to be leading the charge into a hostage situation in a bell-tower. Triela lets them get away with it (even though they spoiled a moment with her handler), her job is going to be to climb said tower.
In Hunterx Hunter the guard dog of the Zaoldyeck estate is a mindless killing machine to anyone who doesn't come in through the front door, and Gon, who is incredibly good with animals and befriended a bear, is scared of her. Oh, and her name is Miké.
Buu deserves special mention as not only does he sound harmless but when after several chapters he finally appears he is a fat pink man wearing sweat pants and a cape... who makes the god of all gods quake in terror. He then proceeds to single-handedly kill each of earth's strongest fighters with no actual effort.
After a series of increasingly powerful and masucline forms Goku and Vegeta turn him into his most basic one: Kid Buu, who looks like a surly teenager... who happens to be the strongest and least restrained form
Battle of the Gods introduces the God of Destruction, who's capable of fighting a Super Saiyan 3 without even trying, made the KING OF SAIYANS use himself as a seat, and his name is Bills.
In one chapter of the Tenchi Muyo! manga, the gang is attacked by a seven foot bear-like creature called a Duodo, which is tough enough to block the Tenchi-ken. Mihoshi takes one look at it, cries out "FLUFFY!" and the creature runs over to her and starts purring like a kitten.
The Seven Swordsmen of the Mist from Naruto are terrifying warriors whose last names mean some type of fruit.
Battle Wolf Terry Cloth may be a cub when Toriko adopts him, but he can still rip apart foes that Toriko had trouble with. Terry later grows up massively, fitting the trope even more. There's also Coco's Emperor Crow Kiss, Sunny's Mother Snake Queen, and the small pink Wall Penguin Yun (named after the sounds he uses) will eventually be as big as its parents (and hopefully not as vicious).
Early in Blood+, we are introduced to the Chiropterans: virtually unkillable monsters created in military experiments that rip apart humans and drink their blood. The military's codeword for them: Mouse.
In MÄR, Dorothy's most powerful Guardian is an enormous black dog that emerges from a crack in reality, looks like death on four legs, and attacks by devouring whatever it fights (including, in one case, Dorothy's opponent). What is Dorothy's nickname for the guardian? "Toto".
The main character in You Are Umasou is a Tyrannosaurus Rex named "Heart".
In The Annotated Mantooth, the giant robot powered by a uranium core was called "World's Greatest Grandpa." It was also built by Hitler, who died in his own Death Trap with man-eating ducks and peanut butter. The entire Mantooth series was made of this.
Similarly, the Anti-Monitor of Crisis on Infinite Earths is not just the biggest bad of DC Comics, but also the biggest bad of all fiction, having eaten thousands of universes. Yet his name manages to be both innocuous and mildly odd.
A recurring character in early 90s Superman comics was a seven-foot-tall female Intergang bruiser called Tiny Bubbles.
Deadpool once killed a tank-grown monster that had gone berserk (greatly pissing off the agency who owned the monster). Said monster's name was Doris.
The Darkwing Duck comics in Disney Adventures featured a newly-made villain in the form of a super-intelligent kitten named Fluffy.
The X-Men villain Sugarman is a grotesque looking head on legs with multiple arms who speciliazes is horrific genetic experiments and hails from the Age of Apocalypse.
And then there's her personally trained attack dog, Mercy, whom she was forced to kill when Darkseid ordered the canine to kill her.
Moreover, you have Glorious Godfrey's sister, the expert assassin Amazing Grace.
Miracleman: An unintentional example given that he started out as a good guy, but the name of the character responsible for the most gruesome massacre in the history of comics? Kid Miracleman.
Empowered: You'd think that in a series featuring characters with names like Demonwolf or Deathmonger, someone who goes by the seeming innocuous name of Willy Pete would be relatively harmless. You'd be wrong. Dead wrong. His name means White Phosphorus.
In Stanley and His Monster, the Monster was later revealed to be a demon called "The Beast with No Name" that was a pariah in Hell for being too nice. When it accidentally bonded to Stanley Dover and became his friend, Stanley gave it the name "Spot". While Spot is a pretty decent fellow, a friendly demon is still a demon.
In the Marvel AdventuresHulk series, Hulk and Rick Jones encounter The Nameless One, a two-headed Eldritch Abomination. One of his heads is certain that they need a name, and finds human ones like "Bob" and "Tom" exotic and appealing. The other head is not amused.
In Orson Scott Card's Ultimate Iron Man, there is a male antagonist named Dolores, which seems to be more of a great-aunt than a villain. Subverted because "dolores" is Spanish for "pains," which is why he chose the name.
The Emiya Clan managed to get Primate Murder, the White Beast of Gaia, First Dead Apostle Ancestor, the creature whose task is to destroy humanity, as a pet. It kind of came as a packaged deal when Altrouge Brunestud forced herself on Shirou as his newest wife. They call him "Primmy."
Naruto fics just love having Naruto refer to Kyuubi, the giant nine tailed fox capable of leveling mountains with a swoop of his tails, as Fluffy. The fox is rarely amused
In a similar vein, Harry Potter fanfics love to make such names for Voldemort, such as Voldisquirrel and Vulturemort.
Dan: I meant no insult, Mr. Croaker, but your fearsome hit wizard is either totally inept at normal history or he's a certified whacko. It's possible he decided to steal the name from a world famous terrorist who was wreaking havoc in the early seventies, but if so, he got the name totally wrong. Just whispering the name of Carlos the Jackal was enough to send governments quivering in terror, but Carlos the Gerbil? The man has taken the name of a small Australian rodent that many people have as a pet. A gerbil is about as dangerous as being attacked by a marshmallow.
The Mr. Black series has a one chapter dark lord named Fred Fredburger the Really Really Bad. Lampshaded when one of the wizards that summons Mr. Black mentions it just doesn't feel right to fear someone with that name,
Fluffy is a 1965 Tony Randall film about the title character, a full grown household dwelling lion.
In Kung Pow!: Enter the Fist, the main (male) villain was named "Betty". It's actually quite a bit worse than that, his name used to be "Master Pain;" he then changed it to Betty.
In Winter's Bone the criminal, prone-to-Ax-Crazy-violence, meth-addicted uncle of the main character is named... "Teardrop".
Not a creature but it still fits the trope: the gun that Kay gives Jay in Men In Black is a tiny little thing that looks rather like a water pistol. It's called a Noisy Cricket. And when Jay fires it the first time, it takes out a wall, and the kickback is enough to throw him back several metres.
In Ice Age 3: Dawn Of The Dinosaurs, there is a giant, fearsome Baryonyx that even scares a T. Rex. Crazy Survivalist Buck names it... Rudy.
In Trick 'r Treat, the monstrous king of Halloween is named Sam. Short for Samhain.
In Reservoir Dogs, Nice Guy Eddie, Mr. Pink, Mr. White, and Mr. Blonde are all crooks.
How to Train Your Dragon: Toothless is a member of the most feared species of dragon that is known to the vikings, though he doesn't get the name until after he's been at least partially domesticated. His teeth are retractable.
In the Katharine Hepburn/Cary Grant screwball comedy Bringing Up Baby, "Baby" is a fully-grown leopard. He's friendly enough, but he's still a leopard.
In Seven Samurai, Toshiro Mifune's character is named Kikuchiyo after the fake papers he has to "prove" he's of noble birth. Unbeknown to him and to the amusement of the others, Kikuchiyo is the name of a little girl. He still kicks lots of ass.
Lilo's social worker in Lilo & Stitch is a huge black man (voiced by Ving Rhames in the movie, no less) who habitually dresses in formalwear and a gold earring... named Mr. Bubbles. Subverted in that his first name is Cobra.
In The Unborn, the spirit of the unborn child terrorizing Odette Yustman's character is named Jumby.
When your name sounds like "Saccharine", people probably expect you to be as sweet as your name, right? Not true for the Big Bad in Tintin, where Mr. Ivan Ivanovich Sahkrine is willing to kidnap, murder, and steal all to find the location of Red Rackham's Treasure. Well, he is Rackham's descendant and possible reincarnation, after all...
In a somewhat meta example, animal handlers, wranglers and trainers often give innocuous-sounding names to potentially dangerous or frightening animals such as snakes, bears and spiders to make actors feel more at ease when dealing with them and to reinforce the controlled nature of such animal action. A spider wrangler who worked on Arachnophobia says that he would call a spider who had to crawl across an actor "Fred" to disarm the actor.
In Spider-Man 2, Alfred Molina had to act opposite four puppeteered robot arms as Doctor Octopus. He nicknamed them Harry, Larry, Floe and Moe.
Other similarly terrifying creatures with cutesy names appear throughout the series; Hagrid has a tendency to treat dangerous supernatural creatures as if they were fluffy little housepets. He's half-giant, and they usually respond quite well to such treatment. The more dangerous the animal, the cuter the name. See Norbert the dragon.
One of these pets, unfortunately, was a subversion, and is what got him expelled, originally, as revealed in The Chamber of Secrets. As a student, he kept a blind Acromantula named Aragog (not a cute name at all) which was blamed for being Slytherin's Monster. (Actually, Tom Riddle simply shifted the blame to Aragog to draw attention from the true Monster, the Basilisk; ironically, spiders are terrified of the Basilisk). Hagrid later helped it escape to the Forbidden Forest; still, Aragog may have caused a disaster even if this didn't happen. When Harry, Ron went to ask it for advice in Chamber of Secrets, it told them what it knew, but had no qualms about trying to attack them with the intent to feed them to its offspring afterwards.
Adora Belle Dearhart. Despite her cutesy name - which she hates - she chainsmokes, prefers golems to people, has a very dry sense of humour, and can do nasty things to your feet with her stilettos.
An Empathic Weapon sort-of example from Dragaera- The owner of the Great Weapon Godslayer thinks that its/her name is melodramatic and instead calls her by the name of the person whose personality she has (from eating her soul, no less). Thus, we get a magical knife that can and does destroy souls entirely accidentally, eliminates magical effects, and was designed to kill the Demon Goddess Verra (who, despite the title, is not a villain, exactly)... and it's referred to as Lady Teldra.
One of the major plots in The Diamond Age revolves about a Chinese crime lord suspected to deal in child trafficking, but he is actually 'rescuing' tens of thousands of abandoned baby girls and raising them in secret over many years, with heavy use of nano technology, to be an army of Tyke Bombs. As the Chinese love to give flowery names to things, he calls them the Mouse Army. Even with some at the age of twelve they become the largest and by far strongest army in the civil war.
The Anti-Hero protagonist of the Burke novels by Andrew Vachss has a hulking Neapolitan mastiff named Pansy. This is intentional as authorities are automatically suspicious of dogs with names like 'Killer' or 'Satan,' and tough guys are reluctant to report that they were savaged by a dog named 'Pansy.'
In the ancient Roman novel The Satyricon, one character has a hulking watchdog whose name translates as "Puppy" and apparently, this was a joke also found in some earlier satirical works. This makes this trope Older Than Feudalism.
A side character in one of the My Teacher Is an Alien books is an astonishingly huge alien that takes up the better portion of a house. He is called Big Julie by the protagonists, the only portion of his true name they are able to figure out. This appears to be a Shout-Out to "Big Julie," a mobster character from Guys and Dolls. To give an idea of Big Julie's proportions, the only thing the characters ever see of him is a gigantic eyeball filling up a doorway into the part of the house he inhabits. When the aliens vacate the house, they extract him by cutting him into bits, beaming those aboard their spacecraft, and putting him back together.
In Good Omens, by Terry Pratchett and Neil Gaiman, Adam, the young man who is fated to become the anti-Christ names his dog "Dog." Dog, however, is a hell hound. This slowly becomes a subverted trope when Dog becomes as harmless and friendly as his name suggests, because this is his name.
In Hiero's Journey and The Unforsaken Hiero, Hiero's morse (a giant, combat-trained, mutant moose/riding animal) is named "Klootz." During one fight, it caves in the skull of an equally-large mutant bear with one kick.
The Dresden Files features Harry's massive, evil-hunter mastiff/dog-a-saurus cross and is actually a Foo dog, which is so reliable in its abilities that his glare could be used as evidence in the highest White Council courts named "Mouse", whose bark can send shocks through multiple dimensions. Dresden describes this as 'every cell of his body flinching' or something like that. It also scares the ectoplasmic piss out of every other supernatural being in the local vicinity. He also survived a hit from a speeding van and was only mildly inconvenienced at worst by a gunshot wound. Unless there's danger present, he's just a Big Friendly Dog. Said dog is far smarter than a human, and in Changes, we find he considers the ultra-powerful wizard Harry HIS familiar.
Shaggydog, a vicious dire wolf, from A Song of Ice and Fire, who had the misfortune to be named by a three-year-old. It's actually one of the most feral of all the dire wolves... which makes sense, as the young Rickon has turned somewhat feral himself due to lack of parental supervision.
In Hannah Tinti's The Good Thief, Ren becomes pals with a man named Dolly, whom he meets under unpleasant circumstances. Somewhat inconveniently for all concerned, Dolly is a murderer-for-hire who has no qualms whatsoever about his profession.
The titular "kittons" of Cordwainer Smith's "Mother Hitton's Littul Kittons" are not very nice at all, and kept heavily sedated to avoid ... accidents.
The Master-Shark from the Young Wizards series, Ed'rashtekaresket, is quickly dubbed "Ed" by one of the wizards.
Most warships built by The Culture. In fact, most ships built by the Culture.
"My name, you see," he said, as though this would immediately reassure her, "is Petal."
The Demonata: Gregor. The giantcockroach. That kills children and eats people while they're still alive. The name is actually a reference to The Metamorphosis by Franz Kafka, proving that Lord Loss at least has a sense of humour.
Keladry of Mindelan has a bad-tempered scarred gelding with a mean streak. He's a small warhorse who is (eventually) trained out of biting people for no reason, but is still worth a squad in combat. After he catches a would-be horse thief's arm in his mouth, Kel tries to dissuade the man by saying "He's not for sale or for stealing. He'll kill you. He's killed men before, he doesn't seem to find it difficult." The horse's name is Peachblossom.
Kitten the dragon (though her "real" name is Skysong). She's a fairly nice dragon, but she is rather badass.
Non-animal example, the Honor Harrington spaceship the HMS Hexapuma, named for the apex predator of his home world, is referred to by its crew as the Nasty Kitty. The crews of various space navies have a tendency to give cutesy nicknames to warships that could de-populate a small planet.
One of the titular genetically-engineered, fanged, clawed, fast-moving, intelligent, bloodthirsty, and very, very hungry creatures in the novel Ancestor by Scott Sigler is referred to in the narration as "Baby McButters." (She was born from an ordinary cow whom one of the human characters named Molly McButters).
In Robert A. Heinlein's The Star Beast, the eponymous critter is called Lummox. Admittedly, 'he' wasn't too impressive ... until after that time he ate a Buick....
Also, Percy calls the Ophiotaurus Bessie....which, while cute, is a monster capable of destroying the gods
And Percy, after seeing the monster Typhon, hopes that he is instead 'Our giant friend, Leroy'
A Dirty Job by Christopher Moore, has the protagonist become the owner of a pair of hellhounds. He finds on their collars the names "Alvin" and "Mohammed".
This appears in the 2nd book of the Monster Hunter International series. One of the protagonists reveals that, years ago as a child, she befriended a Shoggoth, a horrible creature originating from the Cthulhu mythos. She named the creature Mr. Trash Bags and it became friendly with her, probably because she didn't treat it like a monster. It eventually came to care for her and fought to protect her even though she's an adult now. Still, the creature is every bit as horrifying as it was described originally and it's primary goals are killing and eating people.
In Epic by Conor Kostick, Injeborg names a guard dog "Bouncy".
"Bouncy?" B.E. groaned with disgust. "Inny, it's an ethereal guard dog. It can detect astral projections and ethereal walkers, let alone invisible and hidden creatures. It can savage a troll single-handedly, and you've called it Bouncy?"
StarshipTroopers: One of Rico's squadmates is a man nicknamed "Kitten". "Kitten" is an all-round Nice Guy, but he is also a fully trained Mobile Infantryman, and fully capable of killing someone in twenty ways without breaking a sweat.
In The Deed of Paksenarrion, Paksenarrion rides a huge black warhorse, which she recieved as part-payment for a job. The horse will gladly kick and bite anything, and is considered unmanageable by the setting's best horsemen. She calls him Socks.
In Life of Pi, due to a mix-up at its arrival, the Bengal tiger earned the name "Richard Parker", the name of the hunter who actually caught him. The hunter's name on the application was listed as "Thirsty (the intended name of the tiger) None-Given".
Zig-zagged in Temeraire. Most dragons are given impressive Latin namesnote (in the case of the smallest of them, sometimes excessively so). However, Captain Harcourt's egg hatched unexpectedly early, so she had nothing prepared... leading to her dubbing her huge acid-spitting dragon Lily. The name is perfectly fitting, since Lily is just about the sweetest and most gentle character in the series.
Idlewild: What do you call a humanoid with bat wings, claws, and no face? Popeye.
Lizzie is attacked by a mechanical hyena named Tansy in Spider Circus.
Live Action TV
Kittycat the lion from The Addams Family. It seemed harmless (at least it never hurt anyone).
In Drake & Josh when Drake is sent to remedial English, one of the other students there has a big, intimidating Rottweiler named Cuddles.
In the episode with the bratty child actor; she has a big and brutish bodyguard named Citrus.
Buffy Summers, the Vampire Slayer. She's a tiny blonde who routinely breaks necks, chops off heads, slices priest's goods off, and does other things most men named Jed or Dirk would shudder at. This is lampshaded when Wishverse Vampire Xander says "Someone has to talk to her people. That name is striking fear in nobody's hearts." Even her allies can't quite believe it:
Ancient Guardian: What's Your name?
Ancient Guardian: No, really?
Darla. It's such a sweet-sounding name.
"Angel" too, for that matter (it's a shortened version of Angelus, specifically chosen to be an ironic name). However poet-turned-vampire William Pratt specifically takes the name "Spike" to avert this trope, after Angelus tells him that "Willie" doesn't strike the right note of terror.
Tibbles from iCarly, the pooch of Fred/Lucas, described by Freddie as being either a large dog or a small bear.
An episode of Life had a suspect talking about his cat "Fluffy." When Crews returns later, he encounters Fluffy, who happens to be a tiger.
In the episode of MythBusters that dealt with the Hindenburg, the B Story involved the build team annoying some crocodiles, and at one point they were introduced to the three most ornery crocs at the farm where they filmed: Fluffy, Skipper and Bob.
Inverted in an episode of Empty Nest where a small lost dog charms the Weston family while destroying the household and the larger family dog Dreyfuss getting the blame. When the real owner appears, he explains to Harry Weston what the little bastard really is and calls him the appropriately named "Satan".
On The Muppet Show there are quite a few more grotesque looking monsters. The biggest one, 9 feet tall, shaggy, with fangs and beastly strong is named.... Sweetums. Sweetums usually plays characters that really are pretty friendly, once you get past their appearance. In the original Muppet Movie, Sweetums was referred to as "Jack", though he explains "Jack not name, jack job!": He lifts cars for a living.
The original Hellhound; Cerberus the three-headed guardian of The Underworld in Classical Mythology. His name comes from the root indo-european word ḱerberos. It means "Spotted." Hades, Lord of the Underworld; named his dog "Spot."
In Devin Townsend's concept album "Ziltoid The Omniscient," the Sixth Dimensional Planet Smasher is named... Herman. He hates musicals.
ThisGarfield strip featured Fluffy the Fierce. Sure, he was not much taller than any cat that'd fit the name Fluffy but he was described as a legendary ratter. Until he met Matt-the-Rat, that is.
And there is also Muffin the dog, whom a little girl brings Garfield home to.
Starting in 2013 in The Wizard of Id, the Wizard keeps a dragon named Henry as a pet. (Henry is usually friendly, but being a dragon often causes accidents to happen).
The infamous SMILE.DOG picture. Its name may conjure up images of a cute retriever or something similar. If anyone is seriously curious about the picture, there are links as well as more reliable descriptions of SMILE.DOG on the Nightmare Fuel - TvTropes page...
This joke: A burglar has broken into a house and starts looking for valuables. Suddenly, he hears a voice: "I can see you and so does Jesus!" He waves his flashlight around, but can't see anyone. Again, the voice says: "I can see you and so does Jesus!" Then he sees a birdcage with a parrot in it.
Burglar: "Damn, you scared me! Who the hell are you?"
The parrot: "Gilbert."
The burglar: "What idiot names a parrot Gilbert?"
The parrot: "The same idiot who named the rottweiler Jesus."
There've been some variations of this joke, such as the parot being named Moses and/or simply saying "Jesus is watching". Jesus remains a rottweiler, though.
A team of the world's most hardcore counter-terrorism operatives is bought together by the United Nations in an increasingly dangerous world. To signify their multinational identity, this top secret team is given the name [[Rainbow Six Rainbow]].
The Witch-King sits on his vast, evil, bat-winged steed...Pookums.
In Eberron the fringe religion of The Blood of Vol has many sub-organizations like the "Crimson Covenant," the "Order of the Emerald Claw," the "Hornblade Clan," or the "Keepers of Blood. And then there's the much more happy sounding "Cult of Life." Yes, you should start running now.
Forgotten Realms contains a lot of fun. The Old Xoblob Shop (Waterdeep) has a bouncer named Guraim the Gentle Persuader, also useful as a rack for candles. It's an iron golem.
Magic: The Gathering: "To the camp, it was a fierce and loyal protector. To the sentry's youngest daughter, it would always be her Wuv Muffin." - Flavor text for Patrol Hound
You'd think that a creature called The Polka-Dotted Pansyface would be rather harmless, right? In Mortasheen, you'd be very, very wrong. The author reportedly did it as a parody of how people think Ladybugs are cute even though they're vicious predators, and reportedly based its design off of ''the Tyranids''.
In Munchkin, any piece of equipment can be an "x ...OF DOOM" with the right bonus card attached. This occasionally results in a player toting around a Cute Shoulder Dragon...OF DOOM.
Mutant Chronicles: The Prophet of the Great Darkness, the Harbinger of Doom, the only human to carry an unholy Skalak sword and the only individual the followers of all five Dark Apostles respect is named... Billy.
The 50-foot king cobra inside the Indiana Jones Adventure at Disneyland is known as Fluffy to those who work there.
Along the same lines, the roaring, red-eyed, befanged Yeti on the Matterhorn Bobsleds is named "Harold".
To the cast members who work on Fantasmic!, the animatronic dragon Maleficent was named "Bucky". Since the upgrade, its name has been changed to "Murphy" as a shout-out to Murphy's Law.
The horrifying flaming skeletal ghost starring in the Halloween Space Mountain "Ghost Galaxy" overlay is named "Bob".
As a general rule, any Mons game or any game in which you can summon/breed/create monsters which permit naming individuals provides the easy possibility for this, and most players in such a game will, at least once, rename an undead volcano monster "Mr. Splashy".
An enemy in Icewind Dale II had a pet three-headed chimera named "Precious".
The Little Sisters in Bioshock affectionately refer to the hulking Big Daddies as "Mr. Bubbles" or "Mr. B." The Big Daddies are protective enough of the Little Sisters to earn such an affectionate nickname.
BioShock Infinite brings us Elizabeth's bodyguard, a huge mechanical monstrosity with the unimposing name of Songbird.
Tiny Tiger from the Crash Bandicoot games, isn't. He is a hulking genetic mutation engineered by Dr. Cortex created to deal with Crash and is a boss of several games in the series.
In Warcraft III: The Frozen Throne, Rexxar's huge bear is called Misha, which in Russian is a diminutive form of Mikhail and is something a kid is likely to call their teddy bear.
World of Warcraft incorporates an additional Fluffy the Terrible with a powerful ghoul named Timmy. This seems to be based on the child Timmy, whom Arthas meets in the first Alliance mission in Warcraft III, and who is apparently turned into a ghoul when the Scourge attack a few missions later. However, the ghoul's battle cry of "TIIIIIIIIMMMY!!!!" suggests someone else...
Also, Hunters have the ability to tame 'exotic' pets (the bigger, nastier critters in the game). Guess what trope 90% of people use when naming their new beasts?
There's also the NPC Simone the Inconspicuous. Her pet Precious looks like a small wolf at first. However, when she reveals her true form, her pet becomes a huge Fel Hunter named Precious the Devourer.
Later on, there's a boss in a Cataclysm dungeon, a giant core hound named Beauty, with pet smaller core hounds Spot, Lucky and Buster.
Psychonauts features a lake monster known as The Hulking Lungfish: A bizarre, mutated, wart-covered, slime-shedding, ten-foot-tall abomination with a deep, echoing voice. Actually, her name is Linda, and she's quite friendly.
The most menacing-looking character in Phantom Brave is named "Sprout". He's also the penultimate boss of the main game.
In Wizardry 8, in the Mount of Ascension lives Pee Wee, a huge golem.
In Crysis Warhead one of the nanosuit super soldiers has Cupcake as his call sign. You'll know Cupcake when you see him. He's the one handling the explosives and tanking sniper shots.
In the Modern Warfare series, the badass John MacTavish; field commander of Task Force 141, composed of the best soldiers America and the Commonwealth has to offer; has the nickname Soap. He got that nickname before he got to that position, but he still had the nickname while he was a new member of the SAS. The rest of the Task Force has some pretty cool callsigns, but there are some much lesser ones, such as: Cherub, Meat, Taco, Scarecrow, Peasant, Worm, and Driver. While fighting through the streets of Washington in MW 2, you are supported by "Honey Badger", which is an actual animal that makes a perfectly justified name for a heavy armored vehicle with an autocanon that will annihilate anything you point it to.
In Achaea, the terrible Kraken that lurks beneath the ocean wave and crushes entire ships is commanded by the sea god Neraeos.
Neraeos: Good kraken, Fluffy.
And the lurching, undead, murderous Cryptbeast of Thera is affectionately known to experienced players as "Bianca".
In Skies of Arcadia, the cowardly Valuan admiral Alfonso has a war beast named Antonio. Also, Ramirez's massive flagship is called the Monoceros. Translate that from Greek, and you end up with a ship called the Unicorn.
There is also Bonaparte in Suikoden II, a rather small ... thing which can suddenly grow in size and swallow your party members or enemies. In truth, though, if something is named after Napoleon Bonaparte it's quite reasonable to be intimidated...
Kitaniji, the conductor from The World Ends with You. He wears black, has several Kick the Dog Moments with Neku, wants to mass-brainwash... and has the given name "Megumi". A GIRLS name. The agressive variant of the Pig-Noise could count as well.
The SS Tea Cup guard and one of Captain Syrup's most important soldiers in Wario Land 1 and 2 is called Bobo. And this is a creature that looks like a cross between a crow and a dragon, that happens to be bigger than a car in the original game.
Metal Slug 3 has giant monstrous eels named Helen, Linda, Jenny, and Barbie.
DOG in Half-Life 2 is a multi-ton apelike robot that can throw cars and tear Striders apart with its bare hands... and it's equipped with a personality of a dog: Playful, protective and affectionate towards Alyx Vance and her allies.
Dragonfable has Fluffy as the name of the Big Bad's undead dragon. There's also the doom kitten. the one who looks like a kitten but is really an evil summoner of the undead
One can easily invoke this trope in Dragon Age: Origins when naming your Badass Mabari Warhound. One the game's writers dubbed it "Rabbit". Penny Arcade went with "Barkspawn". It's almost certain that some fans have actually named it "Fluffy" at one point.
The name of the Fifth Blight's Archdemon is Urthemiel, the former Old God of Beauty.
"Barkspawn" became an Ascended Meme in The Darkspawn ChroniclesDLC, wherein Alistair gave him that name.
Drakan: Order of the Flame leaves this one to the player's imagination - while you never get to encounter its owner, there's a weapon hidden in a cave in the Wartok Canyons level called "John the Monster's Axe" (and given the kind of world Drakan is and what kinds of enemies are encountered, there's no telling what kind of Monster this John is).
One of the most fearsome Space Pirates in Tachyon: The Fringe is Redship Rory. Jake, being voiced by Bruce Campbell, can't help but make fun of the name the first time they meet (as much as an encounter in space counts as a meeting). Rory doesn't appreciate the humor and sends his Mooks to kill the hero.
The Big Bad of Death Smiles is a Corrupt Corporate Executive turned wizard who was stranded in Gilverado and is trying to get back to the real world, and doesn't care if he has to open hundreds of portals to the demon world to do it. His name? Jitterbug.
Any of the monstrous Summoned Beasts and Demons that hang out around Fluffy Tamer Keelyn in Fall from Heaven. This includes a vicious Imp she named 'Puppy', and a towering, sulphur-smelling, horned Balorg called 'Giggles'.
The third season of the Sam & Max: Freelance Police games introduced the most horrible and fearsome of the elder gods, whose birthing wails shattered the great continent of Pangaea. His name...is Junior.
In Mega Man Legends, the Bonnes have collaborated to create the ultimate killing machine and Mega Man's greatest challenge yet: Bruno!
During his stint as a prisoner of Tabitha's, Raul took to nicknaming a supermutant who wanted him to fix up his toy car "Cuddles".
Speaking of Fallout, there's the helpful Mr. Handy? Such a cute little explosive robot, yes he is!
In the Nazi Zombies storyline of Call of Duty: World At War, the first ever hellhound is named Fluffy.
Dead Rising 2 has a psychopath fight against a hungry tiger, lovingly named Snowflake by her trainer. Played straight at first, but can be somewhat subverted if you tame her.
The bosses in Darius are giant, heavily-armed mechanical fish with frequently silly names like "Little Stripes", "Fatty Glutton", and "My Home Daddy".
The head demons in Shadows Of The Damned are grotesque abominations which can rip you apart in seconds. They have names like George, Christopher, and for the King of Demons himself, Fleming.
The player character of Ace Combat 4, Mobius One, is often times referred to as "the ribbon" or "the ribbon fighter", after the mobius strip design on his plane's tail. Mobius One is more or less singlehandedly responsible for turning the tide of the war, and in a extra mode in Ace Combat 5, is said to be more effective in combat than a squadron of other pilots.
In Ace Combat 6, allied naval warships can play a part in unleashing Macross Missile Massacre on targets of your choosing. The flagship of the allied navy is "Marigold", a Kirov class battlecruiser.
In the Cold War simulator Theatre Europe, you have the option to use a massive nuclear strike that will bring about The End of the World as We Know It. It's called "Fireplan Warm Puppy".
Can be done in Pokémon. You can even subject legendary Pokemon to their embarrassing Fan Nicknames. It helps that many Pokémon evolve into much more scary creatures over time, but start off rather cute, which warrants such nicknames.
Any series with namable Mons or summoned monsters can have this.
In Kid Icarus: Uprising, Viridi named her troops herself. Since Viridi is a kid, this means that the vicious Forces of Nature have such names as "Boom Stompers" and "Bumpety Bombs". Lampshaded in chapter 22.
Pit: Boom Stomper and Bumpety Bomb, eh? You come up with those names yourself? Viridi: Are you getting smart with me? Pit: No, I'm just curious. Viridi: Because I DID come up with those names myself. Aren't they just the cutest? Pit: Right... Cute. Viridi: Bumpety Bomb... (laughs) Have you ever heard anything so adorable?
In Rusty Hearts, the huge skeletal monster that chases the main characters through the tutorial level is named Fluffy. It shows up again as the real boss of the Labyrinth.
In Supreme Commander the Cybran Nation have one of their Experimental units called the Monkeylord, a ridiculous name for such an awesome massive Spider Tank with a huge frikin laser on it.
Far Cry 3 has Buck, a sadistic hitman and Depraved Homosexual rapist. Shortly after you meet him however, his database entry shows that "Buck" is just a nickname. His real name? Bambi.
The protagonist himself also counts. Over the course of the game, Jason Brody goes from hapless everyman at the wrong place at the wrong time to The Dreaded amongst the pirates, who refer and know him only as..."Snow White".
League of Legends has Annie, a little girl who managed to earn her place in a gladiatorial arena of some of the most powerful fighters and mages in the world. How? She managed to enslave a giant, fire-wreathed shadow bear. She calls him "Mr. Tibbers".
One of the vehicles in Jetpack Joyride is a green, fire-breathing metallic dragon called "Mr. Cuddles".
Sluggy Freelance, while having its share of killer rabbits, has a borderline example of this in the form of the large centipede called Fluffy — it's big compared to a human, but it's large for a bug and considered scary and unpleasant by the humans in the strip. (It's the alien Aylee who considers it cute and gives it the name). Later, all its species get labelled "fluffies".
Dragoon in 8-Bit Theater has a pet dragon named Muffin - who, like all dragons, he thinks is a parrot. She is also the world's most evil dragon that founded the order of Dragoons to kill all of the other dragons, without them knowing, and then killed all but one of them.
Something Positive has the cutely named Choo-Choo Bear and Twitchy-Hug. The former, while terribly cute, is a shapeshifter, occasionally prone to fits of psychotic and homicidal violence. The latter was quite clearly homicidal. That's OK, though. Choo-Choo Bear had him shot. Then Davan made the remains into an ashtray.
Looking for Group has the Chief Warlock of the Brothers of Darkness, Lord of the Thirteen Hells, Master of the Bones, Emperor of the Black, Lord of the Undead. His name is Richard. His friends call him "Dick" (at their own risk).
On later days he's picked up the titles "Lord of the Dance" and "Mistress of Magma" as well. He's also the mayor of a small town up the coast, quite scenic in spring... A small town of the undead that's called "Pretty, Pretty Unicorn." It's a work in progress.
The psychotic pink maniac that stars in Fan Fic/Cupcakes is named... Pinkie Pie ...at least in a good mood. Fans call her "Pinkamena Diane Pie" when she becomes her demonic alter ego.
The title character of The Good Witch is named Angel, and her titular role as "the Good Witch" is explicitly to use her powers to help people and do good things. She's a self-centered sociopath who instead devotes her powers exclusively to making her own life better and amusing herself. Namely by transforming people at random into whatever she thinks would be fun, such as repeatedly Gender Bending a specific guy to mess with his head, or converting local kids into clothing for her mother's store. The comic has been described as a Darker and Edgier take on The Wotch.
L's Empire gives one of the main characters the Ultimate Chimera from Mother 3 as a pet and names it Fluffy.
Schlock Mercenary has the former Ob'enn Superfortress starship, the "Post-Dated Check Loan", capable of outgunning whole fleets at full capacity. Its controlling AI is named Petey. This is in deliberate contrast to the absurdly overdramatic names of most of its race's ships. Incidentally, the next ship the Toughs own is the "Serial Peacemaker", which is a glorified troopship entirely unworthy of its awesome name.
The Ob'Enn themselves apply, and cross over with Deathbringer the Adorable. A cute-sounding name for a bunch of sapient koalazoids...who have decided to take up "xenocidal tendencies" as their hat.
Housepets! has a gator named Fluffy, with an apparent history of eating other pets.
The current page image as of June 2012 is Jared and Mr. Fish the Gyarados from Manly Guys Doing Manly Things. To be fair, Mr. Fish was a Magikarp when Jared named him that, so it is an example of the second case of the "sometimes played with by writers" paragraph.
Bud and Brandi from Wapsi Square have a pet sea monster named Stinky.
The villain in Warrior U is a pink unicorn by the name of Hevvin Angelbright. Sure, he's trying to extinguish all life on earth just for the sake of killing (and is living in a den littered with the skulls of his victims), but how can you hate him? A group of unicorns is called a BLESSING!
The Gamer Cat has the main character angering a big, intimidating cat who later reveals his name as "Sweet". He turns out to be calmer once Glitch invites him to play Super Mario 3D World. Sweet choses to play as Peach.
In The Gamers Alliance, Plushiebunny's second form turns into a horrific monster whose appearance makes many heroes wet themselves in fear.
The Salvation War has Yahweh's pet, the first beast of revelations, which is essentially a 200 foot giant leopard with seven heads and ten horns. Its name? Wuffles. The name is practically a throwaway line in Yahweh's court, the humans it was sicced on have yet to identify it other than "ruthless giant killing machine which it takes aerial bombing and tank fire to kill, after it smacks Fort Bragg, and at death it was trying to form a portal to crawl away through". Then it turns out the Scarlet Beast is named Fluffy.
Survival of the Fittest v4 has Kenny the bear, whose one and only appearance on the island so far is attacking and killing an inactive student. It's heavily implied he used to have human owners who kept him in the cage.
In the Whateley Universe, several Ultraviolents (students with a penchant for violence and blood) keep a twenty-foot-long flesh-eating demonic worm as a beloved pet. They call it 'Fluffy'.
From the pages of deviantART, we get the LemonLoaf. Most of this guys weapons qualify as BFS, but he has done some BFG work as well.
Dragon Cave: one dragon species in particular was designed for this. Its release went like this; people picked up eggs with the sweet, unassuming description "This egg is bright. And pink." The hatchlings were sweet, adorable, stood on one leg (and yes, were pink). Alphabetical sort revealed that they began with the letter "f", and everyone was squeeing over the adorable little Flamingo Wyverns. Then they grew up into ferocious, deadly looking (but still pink) monsters that were incredibly violent and territorial.
On Avatar: The Last Airbender , King Bumi's pet "Flopsie" turns out to be a hulking Goat-Gorilla, though he's actually pretty friendly. There's also "Foo Foo Cuddly Poops" who actually is small since he is a baby, but will eventually grow up to be a gigantic sabertooth moose-lion.
Season 3 brings us Sparky Sparky Boom Man, an assassin that shoots explosions from his forehead and works like the freakin' terminator. Fortunately, he later gets the more appropriate name of Combustion Man.
One episode of Sponge Bob Square Pants has Spongebob buying a friend for Gary and naming him "Puffy Fluffy." Only problem is, this critter hates having to share a house with another pet. This provokes Puffy Fluffy into becoming a horrific, hideous monster, almost bordering on Eldritch Abomination, with multiple Sarlacc-like tongues!
Looney Tunes has Gossamer, the Big Hairy Monster from "Hair-Raising Hare". He also appeared in "Water Water Everyhare" under the slightly more imposing name Rudolf. Anything that invokes images of a red-nosed reindeer necessarily isn't imposing, but Rudolf actually would have been to some a pretty frightening name to hear during World War I and II.
An episode of Johnny Bravo had Johnny hatch a dinosaur egg which was accidentally stolen from a museum. What did he name the dinosaur? Mr. Wuggles.
The Dark Lord Chuckles the Silly Piggy from Dave the Barbarian is the living embodiment of both this trope and the Killer Rabbit. He's one of the primary villains of the series and a powerful dark wizard, but he not only has that absurd name, he actually is a small pig.
The Rocko's Modern Life episodes "To Heck and Back" and "Heff in a Handbasket" feature a demon known as Dread Lord Peaches.
Fathering show Animaniacs had Dot's "pet in a box" running gag, where she would offer to show her cutely-named pet that she keeps in a small box to somebody. When the box is opened, out pops a huge and horrible-looking monster.
Played with in Metalocalypse; as governor of Florida, Nathan Explosion is given the opportunity to name a powerful hurricane barrelling towards the state, and he dubs it "Scrambles the Deathdealer".
A subversion, or at least a joke in the same vein: In Quack Pack, Donald Duck was captured by an alien race and sentenced to receive 50 lashes with a "wet noodle." Said noodle was, in fact, a giant serpent with sharp teeth. Although, it did look something like a flat noodle.
L.O.V.E.-M.U.F.F.I.N. member Rodney has a pet fish named Fluffy. Said fish is a piranha.
In one episode of Mighty Mouse, Oil Can Harry tries to charge an exorbitant insurance premium on Pearl Pureheart's circus, to which Pearl declares "Let's see what Theodore thinks about this!", and Harry replies not being afraid of anyone named "Theodore". When Pearl does call "Theodore", loud thundering footsteps are heard, and the door flings open revealing a huge gorilla who then hurls Harry and Swifty out of Pearl's office. "Theodore" is later revealed to be Mighty Mouse in a gorilla suit.
Darkwing Duck: In one episode, Darkwing finds himself pitted against an African tribal wrestler named "He of delicate bone structure" who turns out two be three times Darkwing's size.
In one episode of Doug, the titular character and his friend lost a frisbee in a yard with an Angry Guard Dog named Lady.
Doug: That's not a dog, Skeeter. That's a monster!
In Powerpuff Girls, one of the bad guys is named Fuzzy Lumpkins. While he doesn't look too threatening (apart from when seriously pushed), he is still a very territorial... thing who can fall into Unstoppable Rage territory ("GET OFFA MAH PROPERTAH!").
An episode saw the fat cat find a new home with little girl that tortures him with her unique brand of affection. The girl decided her new pet needs to play with her pre-existing pet, a dog named Boopsie. Expecting another Odie to kick around, Gafield meets a large pitbull, and delivers a timeless line:
Garfield: This... is a Boopsie?!
In the U.S. Acres segment, Wade Duck once had a bull named Fido. Fido remained unseen until the end of the episode and only then his species was revealed to the viewers and Orson's brothers.
The Duck Dodgers episode Back tothe Academy, Dodgers' instructor is a man named Sgt. Emily (voiced by Randy Poffo, AKA Randy "Macho-Man" Savage!). Justified in that theirs is a future with a more lax take on names with gender-specific connotations, and that his Mom was a literature buff.
Kaijudo Tatsurion the Unchained is called Bob by his friends. (He reluctantly accepted the nickname, but still... then again, it's better than what his mother calls him -Bare Bottom) He's also a giant hybrid monster that combines the savagery of the Beast Kin and the firepower of the Armored Dragons, and probably the most badass monster of the series.
Cheryl's pet ocelot on Archer regularly mauls people, especially Archer. Its name is Babou.
There was a Viking warlord known as Ivar the Boneless. Theories about the reason for his name range from impotence to having lost his legs to osteogenesis imperfecta (leaving him with no real use of his legs), and the last one is supported by the chronicled fact that he was carried into battle. The point is, whatever was wrong with him, he was a chieftain and a warrior, and apparently well respected, in a culture where physically weak men were despised. How badass is that?.
The evil Viking king in The Sea of Trolls was called 'the boneless' because he has no spine.
Ragnar Lodbrok or "Hairy-Breeks" ("Hairy-Pants"), one of the most feared and ruthless warlords of the viking era.
Harald Bluetooth, who (retroactively) sounds like a computer nerd: his name was given to the device as he was the one who united the Norse factions in his area, just as the Bluetooth device apparently 'unites' electronics.
In Rome, one of the emperors marched alongside the legions when he was a child. They made the child, a boy named Gaius Julius Caesar Germanicus, a set of armor that included little leather boots. Gaius received the nickname "Bootsy", or "Little Boots". Guess what the Latin wordfor "Little Boots"/"Bootsy" is.
Roman Gladiators would sometimes adopt stage names like "Pearl" or "Puppy", to use this trope.
During World War II the Germans planned to build a 188-ton superheavy tank called the Maus(Mouse). In this case, the name was chosen on purpose so that the Allies wouldn't guess anything about the vehicle if they discovered the name (the Germans had given away a couple of secrets earlier in the war by using code names that were too reflective of the actual devices or operations). They also designed a 1000-ton monster called the Ratte (Rat).
The German sense of humor also gave a self-propelled 150mm (6") gun the name Hummel - the Bumblebee. Its smaller 105mm cousin was called the Wespe - Wasp. To complete the family, the version mounting a deadly 88mm anti-tank gun was called the Hornisse - the Hornet. All were capable of delivering more than just a sting. The trope was subverted when Hitler declared he didn't want his armored vehicles named after insects, and so the Hornisse became the Nashorn - the Rhino. The other two were still called Wespe and Hummel, and they just made sure nobody mentioned that to Hitler.
As modern Germans are not too fond of martial sounding names (they are not destroyers, they are really large frigates), many German army vehicles are named after the smallest and cutest predatory animals like fox, weasel, fennec, marten, lynx, and dingo. Exception are the leopard main battle tank, and the 25 ton grizzly armored truck.
The prize has to go to the British in WW2, who called what was at the time their main battle tank the Valentinenote It was accepted for service on the 14th February 1941. . Its American-built stablemate was initially called the Honeynote /because compared to British tanks, it was spacious, roomy, mechanically reliable and a complete delight in every way. A British general worried that this was an insufficiently martial name ordered that all imported American tanks be given the names of Civil War generals. The fast mobile Honey then officially became the Stuart after the great cavalry general. The Americans appreciated this so much that they officially adopted this naming convention - all American tanks since have been named for famous generals. .
In any online competitive video game, players with names like 'KILLA234' or 'xXDarKLordXx' will be cannon fodder, but players called 'Fluffy Bear' or 'Pink Kitten' will mercilessly slaughter you. Usually it's because the former are overcompensating 13 year olds, while the latter are more mature and experienced players who aren't nearly as self-conscious. Also, because it's twice as funny for the latter to crush the opposition with the name 'Fluffy Bear', especially if the opponents are the former. And if they don't even have a cute name? Nothing will save you from someone called SoccerDad742, JustForFun21, or VolleyballGrrl.
Also in the above image is Cyclone Tracy, the smallest and most compact cyclone on record that completely leveled Darwin, Australia in the 1970s.
Both Lewis Black and Robin Williams talk about unthreatening-sounding hurricanes in their standup acts. Robin talks about hurricane Terrence, which sounds like a "slightly gay" hurricane, and Lew wonders why the fuck anyone would name a hurricane Lenny.
Out of all of these, however, Hurricane Fifi has them all beat. It killed anywhere from 3,000 to 10,000 people in Honduras alone, and caused $1.8 billion in damage—in 1974 dollars, to boot.note That's $8.1 billion in today's money. It went down as the fourth-deadliest Atlantic hurricane on record. And we must emphasize—the hurricane's name was Fifi.
Similarly, there's the Haboob (which is actually Arabic for "strong wind"). Haboobs are monstrous desert duststorms usually caused by atmospheric disruptions. They're not so much destructive as they are disruptive, but they sure are threatening-looking. So the next time you're in Arizona and you see a six kilometer-tall wall of dust flying toward you at 100km/h, just remember: Haboob.
See the real life Fluffy the Terrible here! Admittedly, pythons don't move around that much....
The dinosaur Saichania, which is a large ankylosauroid covered in spikes, horns, and thick, bony plates. Its name actually means "beautiful" in Mongolian.
Less cute, more embarrassing, is the name "Dunkleosteus". Translated, it means "Dunkle's Bone". While it sounds like the sort of name a thirteen-year old with an impressive fluency in Greek might bestow on something, it belongs to a thirty-three foot fish which was equipped with what amounted to a giant, armored staple remover for a head◊.
As an added sardonic humor, several animals with harmless-sounding nicknames are just as badly feared:
The name of the only individual known to have single-handedly exterminated an entire species? Tibbles.
Gustave sounds like one of the least intimidating names ever, right? It's also the name of a 20 foot crocodile in Burundi, Africa that's a notorious man-eater.
According to The Other Wiki, a killer whale in an English zoo became so aggressive towards his trainers that they were forced to clean his tank from a shark cage. The aforementioned whale's name? Cuddles.
And speaking of war machines, how about other ones being given cute nicknames by their drivers/pilots? There's the famous B-29 bomber Enola Gay (named after the pilot's mother) that dropped the big one on Hiroshima in World War II. The last remaining airworthy B-29 is named Fifi.
The U.S. made a habit of giving nuclear devices very innocent names.
The atomic bombs dropped during World War II? Fat Man and Little Boy.
The first thermonuclear test device was named Sausage◊. It weighed 62 tons and exploded with a force of 10.4 megatons. It created a crater 1 mile across and was the fourth most power test done by the U.S.
The device responsible for the third most powerful nuclear test done by the U.S. was named Runt.
The device responsible for the second most powerful nuclear test done by the U.S. was named Runt II.
At 15 megatons, the most powerful bomb ever tested by the U.S. was named…Shrimp◊. It was also the greatest radiological disaster in U.S. history; the exclusion zone for later tests was increased 917,326 square km or about 1% of Earth’s total land area.
One of the most invasive plants in the eastern United States is the Ailanthus tree, commonly known as the Tree of Heaven. While it's pretty, it spreads so quickly that it rapidly chokes out all other plant life, and there is a very good reason that it's acquired the nickname "stink tree."
In general, the military is quite fond of giving elite units deliberately underwhelming and nondescript names as obfuscation, like the Military Assistance Command Vietnam–-Studies and Observations Group (MACV-SOG), which sounds more like the name you assign to a group of sociologists and logisticians. Which was the entire point. The Canadian spec ops unit (yes, they exist, and yes, they are very good at their work) is named Joint Taskforce-2, a name which tells you exactly nothing. And the Special Air Service was named because they wanted the Nazis to think that the SAS was just another parachute regiment.
The Pakistan Army has a long standing tradition of giving "feminine" sounding nicknames to its Artillery guns. Popular names include "Rani" (Queen), "Shazadi"(Princess) and "Soni"(cute girl).
"Katyusha" is a Russian diminutive of the name Yekaterina (="Katherine", so "Katyusha"="Katie"), and there's a popular song about it. It's also the name of rocket artillery that the Russians used in WWII. Imagine if the US Army had called the T34 Calliope the "Clementine" and you have a rough idea.
Speaking of Reds with Rockets, one of their signature weapons was the PP Sh-41 submachine gun, which gave Soviet infantry much More Dakka than their German counterparts. "PP Sh" is pronounced "peh-peh-sheh" in Russian, and the gun was quickly named the papasha, or Daddy.
"Love waves" sound pretty romantic, hem? They are actually the most destructive of seismic waves. The kind that tears down building foundations, brings down bridges and makes railroads wavy. (In case your wondering, geologists aren't sadists, the waves are named after the man who discovered them, Augustus Love).
Russian soldiers have a habit of putting the endearment -ka at the end of their war machines. Which would be rather as if Americans called a tank "Abrams-sweetie".
Admiral Arleigh Burke, terror of the Solomon islands and bane of the Imperial Japanese Navy, whose name now graces the hull of one of the most powerful warships that sails the seven seas. His first name means "Hare-meadow".
Admiral Andrew Baines Cunningham, one of Britains greatest admirals in World War II. His name means "village of the milk pail".
The meaning of the name Manfred is "Man of Peace". Yeah, right.
During WWII, the RAF dropped 4000lb bombs on Germany. The were called "Cookies".
The BLU-82, a 7.5 ton bomb used in Afghanistan to destroy underground bunkers and cavern complexes, is popularly known as a "daisy cutter," probably because it was also used in Vietnam to turn heavily forested areas into helicopter landing zones fast.
Towards the end of World War II, the US Navy introduced an air-to-ground rocket designed to take out bunkers and fortified emplacements. It carried a 500 pound armor-piercing warhead, and went by the name of "Tiny Tim".
During Prohibition, the criminal activity of Detroit was controlled by a ruthless bunch Kosher Nostra known as the Purple Gang.
The Royal Navy had an entire class of warships named after flowers - the "Gladiolus" series. HMS Anemone, HMS Heartsease (another word for "Pansy"), HMS Gladiolus, HMS Carnation, HMS Jasmine, HMS Poppy...
Dangerous drugs often have innocent-sounding nicknames. "Angel dust" means PCP (a Real LifePsycho Serum). "Molly" means MDMA (known to cause psychological disturbances, dangerously high body temperatures, and, in high enough doses, loss of motor control and even heart failure). Perhaps most infamously of all, "roofies" means Rohypnol (a drug slipped into food to sedate people, usually for the purpose of sexually assaulting them).
Another example from the war in 'Nam. The AC-47 was a fixed-wing gunship created by slapping a ton of miniguns to a WW2-era C-47 Skytrain. The U.S Air Force called it "Spooky". The troops who received its air support took to calling it "Puff, the Magic Dragon" after the famous children's song, because when it showed up at night, it filled the sky with great flaming muzzle-flash.
Many dangerous plants have innocuous, even cute sounding names:
Yellow Oleander is known as "Lucky Nut". It is extremely toxic, containing cardiac glycosides.
Aconitum species are often referred to as monkshood. They are used as arrow poisons.
Rosary Peas, despite their pious sounding name, contain abrin - one of the deadliest poisons known.
One of the most unpleasantly spiny plants in the menagerie of unpleasantly spiny plants that covers the southwestern United States and northern Mexico: The Teddy Bear Cholla, so named because when viewed from a distance, the thousands of needle-thin, transparent, barbed spines that cover every inch of the plant make it look like it's fuzzy or has a sort of halo. To give you an indication of how easy it is to get those spines stuck all over you, the other name for the stuff is "jumping cactus."
Belladonna plant's name translates into beautiful woman (because women used to put dilute belladona juice into their eyes to make their pupils dilate). Try telling that to people who knows it better as deadly nightshade
The various incarnations of the Italian Navy have had ships bearing the harmless-sounding Caio Duilio (it sounds harmless and even stupid even to Italians, as long as they don't know who they're named after). Said ships are all warships, including one that, when commissioned, was universally considered the most powerful of the world (she scared the Royal Navy, and the Caio Duilio and her sister Andrea Doria were believed superior to the entire French fleet of the Mediterranean in virtue of having enough firepower to One-Salvo Kill any French ship from outside their range).
In order to maintain operational secrecy, military operations are often given innocuous or even ridiculous names. In some instances, such as in the Invasion of Panama, the United States went so far as to change the name to something cooler after the operation was concluded. Originally, the invasion was given the title "Operation Blue Spoon" while in the planning phase, before becoming "Operation Just Cause" during and after the invasion.
Not even military camouflage is spared from humiliating nicknames. The Russian "Kamuflirovannyi Letnyi Maskirovochnyi Kombinezon" (Camoflagued Summer Deceptive Coveralls, abbreviated to "KLMK") has been given the nickname "sun bunnies". The Swiss "Leibermuster" pattern, meanwhile received the nickname "four-fruit pajamas" while it was in service.
Adam Lanza, perpetrator of the Sandy Hook Elementary School shooting, and killer of 20 children, frequented Internet chatrooms and forums as "Smiggles."
Tonton Macoute (Uncle Gunnysack) is an evil bogeyman in haitian mythologie and it's also the name of the paramilitary force who helped oppress Haiti during the reign of terror of Papa Doc and his son Baby Doc (Yes, these two dictators count as well).
During World War II, the US had a 36 inch mortar called Little David◊, which was designed to test aerial bombs (presumably by first launching them into the air). They floated plans to use the Little Davids as siege mortars during Operation Downfall, but Japan surrendered before the war came to that.