an idiom.
id·i·omˈidēəm/noun1.a group of words established by usage as having a meaning not deducible from those of the individual words (e.g., rain cats and dogs, see the light ).synonyms:language, mode of expression, turn of phrase, style, speech, locution, diction, usage, phraseology, phrasing, phrase, vocabulary, terminology, parlance, jargon, argot, cant, patter, tongue, vernacular; informallingo"these musicians all work in the gospel idiom"2.a characteristic mode of expression in music or art."they were both working in a neo-impressionist idiom"
