Epifunny Share definition Flag n. a hilarious revelation, realization I was in the grocery store today when I had an epifunny - in Chris' mugshot, he was wearing a shirt that read "It Wasn't Me." Epifunny by oldgregmangina January 12, 2009 0 0 Get merch Get the Epifunny mug. Buy Now — $32.95 See more merch