GO MEDIEVAL ON SOMEONE'S ASS Share definition Flag to lose one's temper on, to lose one's emotional equilibrium and act cruel or savage to somebody After the pickle-sniffer winked at Henry, he went absolutely medieval on the fudge packer! GO MEDIEVAL ON SOMEONE'S ASS by weave October 7, 2003 0 0 Get merch Get the GO MEDIEVAL ON SOMEONE'S ASS mug. Buy Now — $32.95 See more merch