Steroid Booty Share definition Flag a girl with a big booty. SB for short. a girl with an abnormally big butt. andrew: have you seen susy's steroid booty(SB)?.. its astonishing !! l0l : orrrr. susy has a SB fo sho ! Steroid Booty by xSMx November 6, 2009 0 0 Get merch Get the Steroid Booty mug. Buy Now — $32.95 See more merch