The act of attempting to be funny on April 1st, but results in you getting your ass beat, dumped by your gf/bf, or making yourself look like a complete dumbass.

Ex 1/ Guy:"I fucked your girlfriend last night when she was over. It was amazing............APRIL FO- *gets ass kicked

Ex 2/ Guy:"Hey babe, look im really sorry, but i had sex with your best friend last night and it was amazing, but i got her pregnant..........APRIL FOOLS!"

Ex 3/ Guy:"Im really sorry your grandparents passed away last night........APRIL FOOLS!"


^"april fail's" in action
by failfooler April 2, 2009
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There are 2 definitions for this:

1) When a complete dickhead tries to play an April Fool's joke on you after midday on the 1st April, or any other time of the year. This becomes obvious when the dickhead says 'April Fools!' after trying to trick you.

2) Anyone that tries to play an April Fool's joke on you, but you see right through it, and to top things off, they say 'April Fools!' anyway, which is just dumb.
1) Dickhead: Hey Chris, you dropped your ipod?
Chris: Did I? *Looks back*
Dickhead: *Slaps Chris over the back of the head* April Fools!
Chris: It's May, dumbass. God, what an April Fail...

2) On April the 1st, this dude comes up to me and tells me my bag's open. Being cautious, I know it's an April Fools joke and just sneer at him. Then, he shouts 'April Fool!' and starts laughing like a retard. That guy's an April Fail!
by April_Failproof April 3, 2009
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When you try to pull off a April Fool's joke and fail horribly.
Indie Radio DJ: Coming up next is Left Behind by Slipknot!
::listeners tune out, song finishes::
Indie Radio DJ: OH HO HO! April Fool's!
Random Guy: Wow, more like April Fail's joke.
by [B]saint April 1, 2009
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