(idiomatic) All or nothing. Probably derived from "shoot duck or no dinner".

(cricket) To score one's first run in an innings. / (idiomatic, Britain, by extension) To do something for the first time.

(simile, vulgar) Extremely tight; mean; excessively thrifty.

plural of duck-billed platypus

Alternative form of water off a duck's back.

(computing, humorous) The tendency of computer users to think the system (software or usage paradigm) they originally started using is better than others.

A duck of the Oxyurinae subfamily.

plural of duck-egg blue

plural of duck-billed dinosaur

(informal) Any ornithopod dinosaur of the family Hadrosauridae.