50 is a nickname for 50 cent.
50 cent is a rapper.
1: ey 50!
50 cent: what's popping son?
Adjective;
The process of describing someone's prediction of an event, after said prediction turns out to be completely the opposite of what they said would happen.
Lew I thought you said Southampton would beat Leicester but they lost 9-0, "yeah I completely 50'd it"
(fiff-tee - bah-mb)
to get 50 kills in a game
"dude, i dropped a 50 bomb and we still lost!"