1the part around the neck of a shirt, blouse, jacket or coat, either upright or turned over: a shirt collar we turned our collars up against the chill a band put around the neck of a domestic animal, used to restrain or control it: dogs for the Deaf are identified by an orange collar and leash a coloured marking resembling a collar round the neck of a bird or other animal:the drake has a narrow black collar a heavy rounded part of the harness worn by a draught animal, which rests at the base of its neck on the shoulders:a shire horse leaning into its collar 2a connecting band or pipe in machinery. 3British a piece of meat rolled up and tied. a cut of bacon taken from the neck of a pig.
4the part of a plant where the stem joins the roots.
seize or apprehend (someone):police collared the culprit approach (someone) in order to talk to them:he collared a departing guest for some last words