Zip  —n. 1 light fast sound. 2 energy, vigour. 3  a (in full zip-fastener) fastening device of two flexible strips with interlocking projections, closed or opened by sliding a clip along them. B (attrib.) Having a zip-fastener (zip bag). —v. (-pp-) 1 (often foll. By up) fasten with a zip-fastener. 2 move with zip or at high speed. [imitative]