A duck that feeds mainly by diving such as the pochard.

A duck that feeds by dabbling in shallow water if subfamily Anatinae, including the mallard and teal.

(historical) A chair used to punish women, especially scolds, by ducking them in water.

(idiomatic) One who is in serious danger or trouble. / (idiomatic) A project that is doomed to failure from the start.

(surfing) To push one's surfboard (usually a shortboard) underwater nose-first, to get the surfer and board under a wave that has broken or is just about to break.

(surfing) The action of duck diving (see verb).

Alternative form of lame duck

(idiomatic) An obvious or unconcealed target.

plural of dead duck

(Australia, countable) The bird Tadorna radjah, a protected species within Australia.