Abreviation of "heads up for"
1. Often used when someone wants to call others attentions and respect for some matter.
2. To warn a dangerous situation.
1.
Friend 1: Hey, Dude, I've been looking for you all weekend! What the hell were you doing and fucking where?
Friend 2: Sorry, Dude, my girlfriend's parents travelled so I went there and stayed. HU4 the newest non-virgin in this room!
by Gabbi_Sky March 23, 2010
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