Colloquialism

[kə'ləʊkwɪəlɪz(ə)m] or [kə'lokwɪəlɪzəm]

(noun.) a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech.

Inputed by Celia--From WordNet

(n.) A colloquial expression, not employed in formal discourse or writing.

Editor: Percival