G.D.M.F.S.O.B. Share definition Flag Acronym for god-damn mother fuckin' son of a bitch. Joe called Sally a G.D.M.F.S.O.B. after she tried a dirty-sanchez Hitler combo on him. G.D.M.F.S.O.B. by Russian Love April 30, 2005 0 0 Get merch Get the G.D.M.F.S.O.B. mug. Buy Now — $32.95 See more merch