Solecism

Part of speech: noun (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.

Synonyms: Barbarism; impropriety; absurdity.