idiom > define

noun

• A manner of speaking that is natural to native speakers of a language.
  • synonyms: parlance
• The usage or vocabulary that is characteristic of a specific group of people.
  • usage: "the immigrants spoke an odd dialect of English"; "he has a strong German accent"; "it has been said that a language is a dialect with an army and navy"
  • synonyms: dialect, accent
• The style of a particular artist or school or movement.
  • usage: "an imaginative orchestral idiom"
  • synonyms: artistic style
• 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

• (n.) Dialect; a variant form of a language.
• (n.) An expression conforming or appropriate to the peculiar structural form of a language; in extend use, an expression sanctioned by usage, having a sense peculiar to itself and not agreeing with the logical sense of its structural form; also, the phrase forms peculiar to a particular author.
• (n.) The syntactical or structural form peculiar to any language; the genius or cast of a language.