U.S.A.B Share definition Flag Pronounced as You-sob. Stands for Ugly Son of A Bitch. Reffered as someone. Did you see that U.S.A.B? That's one hell of U.S.A.B U.S.A.B by iVanH June 12, 2008 0 0 Get merch Get the U.S.A.B mug. Buy Now — $32.95 See more merch