Idiom

n.	1.	The syntactical or structural form peculiar to any language; the genius or cast of a language. Idiom may be employed loosely and figuratively as a synonym of language or dialect, but in its proper sense it signifies the totality of the general rules of construction which characterize the syntax of a particular language and distinguish it from other tongues. - G. P. Marsh. By idiom is meant the use of words which is peculiar to a particular language. - J. H. Newman. He followed their language [the Latin], but did not comply with the idiom of ours. - Dryden.
	2.	An expression conforming or appropriate to the peculiar structural form of a language. Some that with care true eloquence shall teach, And to just idioms fix our doubtful speech. - Prior.
	3.	A combination of words having a meaning peculiar to itself and not predictable as a combination of the meanings of the individual words, but sanctioned by usage; as, an idiomatic expression; less commonly, a single word used in a peculiar sense. It is not by means of rules that such idioms as the following are made current: "I can make nothing of it." "He treats his subject home." Dryden. "It is that within us that makes for righteousness." M. Arnold. - Gostwick (Eng. Gram. Sometimes we identify the words with the object - though by courtesy of idiom rather than in strict propriety of language. - Coleridge.
	4.	The phrase forms peculiar to a particular author; as, written in his own idiom. Every good writer has much idiom. - Landor.
	5.	Dialect; a variant form of a language.

Noun	1.	idiom - a manner of speaking that is natural to native speakers of a language Synonyms: parlance
	2.	idiom - the usage or vocabulary that is characteristic of a specific group of people; "the immigrants spoke an odd dialect of English"; "he has a strong German accent" Synonyms: dialect, accent
	3.	idiom - the style of a particular artist or school or movement; "an imaginative orchestral idiom" Synonyms: artistic style
	4.	idiom - an expression whose meanings cannot be inferred from the meanings of the words that make it up Synonyms: idiomatic expression, phrasal idiom, set phrase, phrase

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