Definition of: idiom

(id′ē·əm) noun
1. An expression peculiar to a language, not readily analyzable from its grammatical construction or from the meaning of its component parts, as to put up with (tolerate, endure).
2. A speech pattern, dialect, or language characteristic of a certain group, class, trade, region, etc.: legal idiom.
3. The peculiar genius or spirit of a language.
4. Specific character, peculiarity, or style, as in art or literature. See synonyms under LANGUAGE. [<L idioma <Gk. idiōma peculiarity, property <idioein appropriate <idios one's own]