idiom
     n 1: a manner of speaking that is natural to native speakers of a
          language [syn: {parlance}]
     2: 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" [syn: {dialect},
         {accent}]
     3: the style of a particular artist or school or movement; "an
        imaginative orchestral idiom" [syn: {artistic style}]
     4: an expression whose meanings cannot be inferred from the
        meanings of the words that make it up [syn: {idiomatic
        expression}, {phrasal idiom}, {set phrase}, {phrase}]
Source: WordNet® 2.0