Rel Share definition Flag A friend, buddy, pal, comrade, mate, etc…; an abbreviation of the word relative; originally used in mockery of terms like cuz or bro *Between roommates* Eduardo- (Enters room) How’s it going man? Scott- Oh, hey. ‘Sup rel? Rel by cyc1ops May 7, 2008 0 0 Get merch Get the Rel mug. Buy Now — $32.95 See more merch