It can also mean the person that furffed. I've been hearing this more and more. Some say it stands for "F'd Up a Really Fantastic Friendship".
As in, "Gee Harold why you gotta be such a furff? You've known her since gradescool!"
by nonfurff January 17, 2004
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When you take advantage of a friend of either sex at a party who's drunk and willing.
Last night, my best friend and I ended up in a furff after about 5 drinks.

At that party last week I furffed Sally. She'll never talk to me again.
by WG December 22, 2003
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