Calling Me a Logarithm

"Ollendorf: I acknowledge freely that I have had hard feelings against Mr. Ballou for abusing me and calling me a logarithm, which is a thing I do not know what, but no doubt a thing considered disgraceful and unbecoming in America..."

- Mark Twain's Roughing It

Alice is speaking to Bob about something. In the course of the dialogue, Alice calls Bob eloquent, or valiant, or perhaps "a Badass". Not knowing what a badass is, Bob demands to know why she thinks he has hemorrhoids.

A Comedy Tropes about people being offended by words they don't know. Often, but not always, a case of Compliment Backfire. See also You Keep Using That Word for another way to take an unfamiliar word, invent a meaning, and assume it's the one everybody uses.

Pretty much the inverse of Insult Backfire. Contrast Malaproper.

Comics

 * In a Running Gag, Groo the Wanderer becomes violently enraged whenever someone calls him a "mendicant," even though he has no idea what the word means.

Film
"Donatello: You're a claustrophobic. Casey Jones: Hey, you want a fist in the mouth? I've never even LOOKED at another guy!"
 * In the French film Les Choristes, one of the teachers in a boarding school for delinquents wants to start a boys' chorus so he tests out each boy's voice. To the most feared delinquent of them all, he says, "You're a very good baritone." The kid tries to kick his ass.
 * The Teenage Mutant Ninja Turtles movie has one "insult" (actually a description) traded for another. Casey Jones reveals that he's uncomfortable spending the night in the Turtles sewer lair.

"Shadow: Chance, you're a genius! Chance: I am not! What's a genius?"
 * One of the students in Renaissance Man misunderstands the word "oxymoron" and asserts that he "ain't no ox-moron".
 * In Homeward Bound:

"Dr. Poole: She seems to have such nicely rounded diphthongs! Snaps: That's what got her into this jam!"
 * In the film of A Series of Unfortunate Events, the orphans make pasta puttanesca for Count Olaf and his fellow actors. When Klaus announces that they've made "puttanesca," Olaf responds "What did you call me?"
 * It could also be a Bilingual Bonus or even Getting Crap Past the Radar, since the name "puttanesca" actually is derived from the word for a prostitute.
 * The character of Raymonde in the French film Hôtel du Nord is mainly famous for indignantly asking her interlocutor « Atmosphère ? Atmosphère ? Est-ce que j'ai une gueule d'atmosphère ? » (Atmosphere? Atmosphere? Do I look like an atmosphere to you?)
 * Two examples from Oscar include:

"Connie: Even in the old days he was known as an honest crook. Dr, Poole; That's an oxymoron. Connie: Gee, you shouldn't oughta said that, Doc. Snaps: Yeah, leave Connie alone. He does the best he can."
 * and

Literature
""I hate it worse and worse every day!" cried Randolph. "You are like the infant Hannibal," said Winterbourne. "No, I ain't!" Randolph declared, at a venture."
 * Mark Twain's Roughing It is the Trope Namer
 * Discworld:
 * Interesting Times: "He called me venerable!"
 * In Feet of Clay, Vimes is told that Nobby is entitled to a coat of arms. He goes back to the Watch House and says "Nobby, you're armigerous!" This is taken by Nobby to mean, while not quite an insult, something for which he might need "a special shampoo." When one barman is informed that Nobby is a Peer, he assumes it is used in the verb sense rather than the '-of the realm' sense.
 * In Unseen Academicals, Glenda is offended when Mr. Nutt tries to flatter her by calling her "fecund". After hastily looking the word up she's merely embarrassed, and Glenda gently explains to Nutt why that might not be a good word with which to compliment women.
 * In The Mysterious Benedict Society and the Perilous Journey, Sticky's girlfriend dumps him for remarking on her "pulchritude." It means beauty.
 * Daisy Miller, when the Annoying Younger Sibling is talking about how he hates Rome:

Live Action TV
"Chief: Max, Hymie is a cybernaut. Max: What's his religion got to do with it? 4:00-4:05"
 * On Get Smart, during a Hunting the Most Dangerous Game episode the bad guy called Max a "Homo sapien. " Max replied: "Hey, I'm as normal as the next guy."
 * Another Get Smart example deals with Hymie the Robot, and why he shouldn't date the Chief's niece.

"Max: Hymie is a cybernaut. Phoebe: Uncle Max, I'm ashamed of you. A person's religion doesn't make any difference. 1:50-2:00"
 * Later on, after Max learns that the Chief's niece has fallen for Hymie:

"Giles: I suppose there is a sort of...Machiavellian ingenuity to your transgression. Xander: I resent that! Or possibly thank you."
 * A sketch on The Tracey Ullman Show had a girl asking her friend what 'satiated' meant, and then phoning her boyfriend to apologise for what she had done after he had said he was satiated following sex.
 * The Buffy the Vampire Slayer episode "Bad Eggs":

"Wesley: The cross obviously doesn't affect me or our friend, (points to Gunn) the pugilist. Gunn: Oh, yo' ass better pray I don't look that word up."
 * And over on Angel, after everyone loses their memories:

""Billiards, darts, these are things you're adroit at, Sam." "Listen, nobody calls me a 'droit'.""
 * In an episode of That '70s Show, Hyde is trying to teach Fez to pick up girls by being cool and aloof. Fez hears it as Hyde calling him a "loof", which is apparently an insult in his native language (whatever the heck it is).
 * A recurring sketch from the series Balls of Steel features the "Militant Black Guy", who always takes great offense to what he thinks are racial slurs, but are obviously totally innocent terms in context. For instance, when he enters a bakers and is shocked to hear the cake he asked for is called a black forest gateaux.
 * On an episode of Castle, a safe deposit box belonging to a mob figure is broken into. The mobster claims it contained his stamp collection. One of the cops asks him how long he has been a philatelist. His response is "Hey! I don't roll that way!".
 * Cheers:


 * On Psych season four, Juliet calls Shawn "prophetic," who childishly retorts that she's the one who's prophetic.

Theatre

 * In The Pirates of Penzance, Major-General Stanley asks the pirates "You're not thespians, are you?". Depending on the production, the pirates reaction to this can be priceless.

Video Games

 * The Nameless Mod has this quote from a Board Guest: "I can't believe the moderators won't do anything! Every time I ask something, people call me a faq!"

Western Animation
"Squit: I wanna be a tough bird, like you, Pesto. Pesto: Whaddaya mean by that? Squit: I just mean you're tough, that's all. Pesto: Are you sayin' I'm an overdone piece of meat? Is that what you're sayin'?"
 * The Cow and Chicken episode "Black Sheep of the Family" features the... well, black sheep of the family (a literal black sheep). Everyone would mistake his Sesquipedalian Loquaciousness for insults or swearing.
 * A Running Gag on Pinky Elmyra and The Brain is Elmyra scolding Brain for being a "naughty-waughty potty mouth" whenever he uses a big word she doesn't understand.
 * On Animaniacs, Pesto from the "Goodfeathers" cartoons uses something similar to this trope. From their first episode:

"Squidward Could you not stand so close? You're making me claustrophobic. Patrick: What does claustrophobic mean? Spongebob: It means he's afraid of Santa Claus. Squidward: No, it doesn't. Patrick: Ho, ho, ho! (giggles) Spongebob: Stop it, Patrick; you're scaring him! Patrick: Ho, ho, ho! Squidward: It's not working, Patrick. Patrick: Darn."
 * Also happens with "Rita and Runt". Rita describes Runt's actions as 'chivalric'. Runt apologises.
 * This is probably how the word "nimrod", originally the name of a great hunter from the Bible (and thus a nickname for a hunter), became to mean "a fool, a klutz." In a popular Looney Tunes short, Bugs Bunny called Elmer Fudd a "poor little Nimrod," and the kids watching it thought it was some fancy insult they never heard before.
 * SpongeBob: After Squidward finds himself accidentally stuck down a deep well with Spongebob and Patrick:

"Edd: Pure fiction, Eddy. Your exaggerated tale can only be described as cockamamie! Ed: Tsk, tsk, tsk, I have never heard such language."
 * Inversion: In Disney's Beauty and the Beast, Belle chuckles and tells Gaston that he is "positively primeval". Gaston, having no idea what she meant, takes it as a compliment, and thanks her for it.
 * Done a few times in Ed, Edd 'n' Eddy, such as Edd's reaction to Eddy's side of the story in "Once Upon An Ed"


 * In one episode of Time Squad, after arriving in Sweden, a guy approaches Tuddrussel and says "God morgon!". Tuddrussel automatically assumes he's being insulted and decks the guy. Larry 3000 scolds him and says the guy said, "Good morning."

Other

 * "I'm not a homophone! I write Slash Fic!"

Real Life

 * There've been a number of highly publicized cases where people used the word "niggardly" and were accused of racism by people who Did Not Do the Research and assumed it was a racial slur. It really means "cheap" or "stingy", and is, in fact, completely unrelated to the n-word, having been borrowed from the Norse language.
 * Fark filters the n-word to "attractive and successful African-American", and filters its phonetic cousin to "nubian". Thanks to the Scunthorpe Problem, "niggardly" becomes "nubianrdly" on Fark.
 * Dallas County, Texas Commissioner Kenneth Mayfield (white) had to explain what a black hole is when fellow Commissioner John Wiley Price (black) took it as a racial slur, prompting Judge Thomas Jones (also black) to demand that Mayfield apologize for his 'racist' comment.
 * Similarly, a University of Pennsylvania student in 1993 got charged with racial harassment when he shouted at a crowd of mostly black sorority sisters creating a ruckus outside his dorm, calling them "water buffalo". While under prosecution he explained the term comes from Hebrew slang, "Behema", used by Jews to refer to a loud, rowdy person.
 * This story on (The Customer is) Not Always Right, where a cashier uses the word "oxymoron" and a customer thinks the cashier insulted him.
 * The NAACP thought that a "You mad, bro?" sign was a racial attack against the losing team.
 * Apocryphally, George Smathers defeated Congressman Claude Pepper in a 1950 Congressional election by saying that he was a 'known extrovert', that 'his sister was a thespian', and that he practiced 'nepotism' with her. While the last one is a legitimate criticism of a politician, the first two makes you wonder just how ignorant the district voter base could possibly have been.