Mother Booty Share definition Flag lumpy butt rather saggy. on a young teenage girl mistaken for a mother in her late 50s. not a good trait. "Gaby those jeans give u a mother booty." Mother Booty by sjdriouaxfkl;jawldakkioottsaa December 3, 2009 0 0 Get merch Get the Mother Booty mug. Buy Now — $32.95 See more merch