Gully Gul"ly, n.; pl. Gullies. [Formerly gullet.] 1. A channel or hollow worn in the earth by a current of water; a short deep portion of a torrent's bed when dry. 2. A grooved iron rail or tram plate. [Eng.] Gully gut, a glutton. [Obs.] --Chapman. Gully hole, the opening through which gutters discharge surface water.