Duck1  —n. (pl. Same or -s) 1 a swimming-bird, esp. The domesticated form of the mallard or wild duck. B female of this. C its flesh as food. 2 score of 0 in cricket. 3 (also ducks) colloq. (esp. As a form of address) dear. —v. 1 bob down, esp. To avoid being seen or hit. 2 a dip one's head briefly under water. B plunge (a person) briefly in water. 3 colloq. Dodge (a task etc.).  like water off a duck's back colloq. Producing no effect. [old english]