Толковый словарь английского языка - idiom

noun Etymology: Middle French & Late Latin; Middle French ~e, from Late Latin ~a individual peculiarity of language, from Greek idiōmat-, idiōma, from idiousthai to appropriate, from idios Date: 1588 1. the language peculiar to a people or to a district, community, or class ; dialect, the syntactical, grammatical, or structural form peculiar to a language, an expression in the usage of a language that is peculiar to itself either grammatically (as no, it wasn't me) or in having a meaning that cannot be derived from the conjoined meanings of its elements (as Monday week for “the Monday a week after next Monday”), a style or form of artistic expression that is characteristic of an individual, a period or movement, or a medium or instrument