1 [C] (informal) a thing that is useless, especially because it does not work correctly:
Two of the fireworks in the box were duds.
2 (duds) [pl.] (slang) clothes
adjective [onlybeforenoun] useless; that does not work correctly:
a dud battery * a dud cheque (= written by sb who has not enough money in their bank account)
