failure vs dud

failure and dud both are nouns.

Word	Noun	Adjective	Verb	Adverb
failure	Yes	No	No	No
dud	Yes	Yes	No	No

As nouns, dud is a hyponym of failure; that is, dud is a word with a more specific, narrower meaning than failure:

Other hyponyms of failure include bankrupt, insolvent, flash in the pan, flop, washout, underdog.

failure (noun)	dud (noun)
an act that fails	an event that fails badly or is totally ineffectual
an unexpected omission	an explosion that fails to occur
an event that does not accomplish its intended purpose	someone who is unsuccessful
a person with a record of failing; someone who loses consistently
lack of success
loss of ability to function normally
inability to discharge all your debts as they come due

failure (adjective)	dud (adjective)
	failing to detonate; especially not charged with an active explosive