E.G.O. Share definition Flag Performing oral sex upon a female. (E)ating a (G)irl (O)ut. Sounded out (Ego, as in "He has a huge ego. He needs to get over himself.") My girlfriend wants E.G.O., but I'm just not comfortable enough with her. E.G.O. by BirdintheHand September 2, 2010 0 0 Get merch Get the E.G.O. mug. Buy Now — $32.95 See more merch