A theory that subscribes to the notion that there are only 2 outcomes to any kind of situation. It either will happen, or it won't, no matter how unrealistic. There is therefore 50% chance either way.

Also used to piss someone off, in an un-winnable argument.
Anybody: Oi, Gimp, Scunthorpe Utd will win the Champions League within 3 years.

The Gimp: No they won't, Man Utd will.

Anybody: Fuck off Gimp. 50/50 theory says there is a 50% chance they will. Its simple, they either will or they won't, there are only 2 possible outcomes so fuck off!
by Steeman May 07, 2005
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A fart in which you force to the point where it's either gonna be a fart or a poop
Ethan tried to fart and ended up shitting his pants. Looks like he got the bad end of a 50 50 fart.
by 50 50 fart July 09, 2015
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FIDDY in australia a $50 bag of weed is pronounced fiddy
by MaF July 27, 2003
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A magazine that uses the words 'throbbing shaft' and 'clitty' a lot along with a load of naked pictures of hairy older ladies.
Geraldine grabbed hold of Jeff's throbbing shaft whilst he played with her pulsating clitty. Says the 50+ mag people
by Hobophobic April 18, 2006
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A reference to the rate at wich trans-secuals attempt suicide.
Trans-sexual: You're a racist homophobic bigot!
Annoyed person: Just shut up and join the 50%.
by Speed Terrorist October 10, 2020
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A reference to the suicide attempt rate by trans-sexuals.
Trans person: You're a homophobic white supremacist!

Richard Spencer: Go join the 50% you walking vegetable.
by Speed Terrorist October 10, 2020
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