1. idiom, saying; expression; group of words that functions as a single unit (Grammar). formulate in words, express in words; express in a certain manner. phrasephrase, v. t. [imp. & p. p. phrased ; p. pr. & vb. n. phrasing.] [cf. f. phraser.] to express in words, or in peculiar words; to call; to style. these suns -- for so they phrase 'em.phrase phrase, v