noun.
The quality of being improper; unfitness or unsuitableness to character, time, place, or circumstances; unseemliness: as, impropriety of language or behavior.
noun.
That which is improper; an erroneous or unsuitable expression, act, etc.
noun.
Synonyms Indelicacy, unseemliness. Mistake, blunder, slip.—Barbarism, Solecism, Impropriety. In treatises on rhetorical style these words have distinct meanings. “Purity … implies three things. Accordingly in three different ways it may be injured. First, the words used may not be English. This fault hath received from grammarians the denomination of barbarism. Secondly, the construction of the sentence may not be in the English idiom. This hath gotten the name of solecism. Thirdly, the words and phrases may not be employed to express the precise meaning which custom hath affixed to them. This is termed impropriety.” (G. Campbell, Philos. of Rhetoric, ii. 3, Pref.) “In the forms of words, a violation of purity is a barbarism; in the constructions, a violation of purity is a solecism; in the meanings of words and Phrases, a violation of purity is an impropriety.” (A. Phelps, Eng. Style, i.) Examples of barbarisms in English are heft, pled, proven, systemize; of solecism, “Who did you see?” of improprieties, “There let him lay” (Byron, Childe Harold, iv. 180), and the use of enormity for enormousness, or of exceptionable for exceptional.