cross as a bear with a sore bum Share definition Flag Easily angered. Lookin' fer a fight! Child: I hate math homework!! Parent: Now, now... you're as cross as a bear with a sore bum. cross as a bear with a sore bum by Pousquella April 20, 2018 0 0 Get merch Get the cross as a bear with a sore bum mug. Buy Now — $32.95 See more merch