UK usage

1) Something that's flawed or faulty

2) To duff up, to assault, beat up etc
He sold me a duff DVD so I duffed him up.
by black flag May 31, 2004
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Get off your duff and help me with these dishes!
by Anonymous January 3, 2003
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A unattractive female who is always seen with another female who is marginally more attractive. It is usually impossible to score with the hotter female without the duff receiving her fair share of the action.
Damn! I so wanna tap that chick.. but goddamn, she always has that duff Nicole hanging off her. Look at that fat mess!
by Steve0 August 21, 2004
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marijuana that has already been run through a vaporizer at least once.
all i've got left to vaporize is some duff from last week, but we can still get pretty high.
by stoner June 18, 2006
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"Yo did you see Hilton duff Chino in the face"

"Chino is bleeding because he got duffed so hard"

"Some would should duff that kid, Chino, in the face"
by Douch B. September 28, 2007
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A brand of cool US Skate shoes.
Yo man, you see those dope Duff Roadrunners? Way Fresh!!
by PHIVOLCS March 24, 2004
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Dark brown or black cannabis remaining in a vaporizer bowl after vaporizing. The duff, which still contains some THC, is recycled rather than discarded by stingier enthusiasts.
Whoa, don't toss that duff, man! I'm saving that to make hash.
by John Woods August 25, 2008
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