dud (n.)

1825, "person in ragged clothing," from duds (q.v.). Sense extended by 1897 to "counterfeit thing," and 1908 to "useless, inefficient person or thing." This led naturally in World War I to "shell which fails to explode," and thence to "expensive failure."

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Definitions of dud from WordNet
dud (n.)
someone who is unsuccessful;
Synonyms: flop / washout
dud (n.)
an explosion that fails to occur;
Synonyms: misfire
dud (n.)
an event that fails badly or is totally ineffectual;
the meeting was a dud as far as new business was concerned
Synonyms: turkey / bomb
dud (adj.)
failing to detonate; especially not charged with an active explosive;
he stepped on a dud mine