flop, dud, washout -- (someone who is unsuccessful)
misfire, dud -- (an explosion that fails to occur)
turkey, bomb, dud -- (an event that fails badly or is totally ineffectual; "the first experiment was a real turkey"; "the meeting was a dud as far as new business was concerned")
Overview of adj dud
The adj dud has 1 sense
dud -- (failing to detonate; especially not charged with an active explosive; "he stepped on a dud mine")