Bagacum Share definition Flag a very unfortunately named town on the north-east border of france, the name is celtic in origin. guy 1: "I'm going to visit my cousin in Bagacum this summer" guy 2: "LOL, incest much?" Bagacum by longjohnawesome June 21, 2010 0 0 Get merch Get the Bagacum mug. Buy Now — $32.95 See more merch