HFP stands for Hands-Free Pee, the phenomenon in which no hands are needed to urinate. While women are (usually) regularly capable of HFP, men who stand up to urinate often miss. HFP in men is usually attributed to a mild boner that perfects the angle of urination; however, other factors may affect HFP.
Experiencing HFP is said to make a man's day.
Jay: "Dude! You just came out of the bathroom without washing your hands! What gives?"
Greg: "I didn't have to! I got a HFP, so all that I had to do was whip it out and tuck it in! I'm gonna cancel that 4 o' clock suicide now!"
Jay: "Swell!"
by Nuclear Tank Factory June 10, 2009
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HFP- Hella Fuckin Pissed

Levels of being HFP can be on a scale of 'pissed off' to 'eye gouging rage.'
Person 1: I was HFP when that bitch walked up to me at the party and acted like nothing had happened

See bat shit insane
by hellaskep June 21, 2010
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Also known as High Fat Potential. If a girl's mom is obese or is a fat slob, that girl has HFP.
Even though Ellie is hot and petite, her mother must weigh 250. Ellie has HFP--if you marry her, in 20 years, watch out.
by Indybreadman March 15, 2017
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