"Jagoff" (sometimes "
jag-off") seems to have originated in Pittsburgh but is also recognized in the Midwest as
slang for an inept, feckless, contemptible, or generally worthless
person, a loser, a "schlemiel."
The term is almost certainly derived from the verb "jack off" (through noun "jack-off") as in "
masturbate," but somewhat like the British use of "wanker," it is usually not a direct comment on self-pleasuring, but more of a general term of contempt or deliberate abuse. Like "wanker," "jagoff" is somewhat vulgar and not to be used lightly, and avoided in cultivated speech, but is recognized by all in the regions in which it has currency.
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