Solecism

n.	1.	An impropriety or incongruity of language in the combination of words or parts of a sentence; esp., deviation from the idiom of a language or from the rules of syntax. A barbarism may be in one word; a solecism must be of more. - Johnson.
	2.	Any inconsistency, unfitness, absurdity, or impropriety, as in deeds or manners. Cæsar, by dismissing his guards and retaining his power, committed a dangerous solecism in politics. - C. Middleton. The idea of having committed the slightest solecism in politeness was agony to him. - Sir W. Scott.

Noun

1.

solecism - a socially awkward or tactless act Synonyms: faux pas, gaffe, slip, gaucherie

Irish bull, anachronism, anacoluthon, antiphrasis, argument, argument by analogy, argumentum ad baculum, argumentum ad captandum, argumentum ad hominem, bad case, barbarism, begging the question, bloomer, blooper, blunder, boner, boo-boo, boob, botch, breach, break, bull, bungle, catachresis, circular argument, claptrap, corruption, crowd-pleasing argument, empty words, error, fallacy, fault, faux pas, flub, fluff, folk etymology, formal fallacy, fumble, gaffe, gaucherie, grammatical error, hypercorrection, hyperform, hysteron proteron, impropriety, incongruity, inconsistency, indecorum, indiscretion, infelicity, insincere argument, lapse, logical fallacy, malaprop, malapropism, marrowsky, material fallacy, mere rhetoric, misconstruction, mispronunciation, missaying, mistake, misusage, moonshine, non sequitur, paralogism, petitio principii, philosophism, pseudosyllogism, slip, sophism, sophistry, spoonerism, stupidity, ungrammaticism, verbal fallacy, vernacularism, violation, vulgarism, weak point