Nouns

(n)flop, dud, washoutsomeone who is unsuccessful
(n)misfire, dudan explosion that fails to occur
(n)turkey, bomb, dudan 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”

Adjectives

(s)dudfailing to detonate; especially not charged with an active explosive“he stepped on a dud mine”