auitb Share definition Flag An acronym for "All Up In This Bitch". Used while typing. Other forms can include uitb; Up In This Bitch. Frat boy 1: "Yo bro, we need some more drinks auitb" Frat boy 2: "K lol" auitb by Gnarly_Party May 4, 2015 0 0 Get merch Get the auitb mug. Buy Now — $32.95 See more merch