bust-up I. \ˈ ̷ ̷ˌ ̷ ̷\noun (-s) Etymology:bust up, v. 1.: a breaking up or apart < the bust-up of camp > < the bust-up of their marriage > 2.: a big party or celebration < there'll be an awful crowd — a regular bust-up — Norman Douglas > II. noun chiefly Britain: an outbreak of dissension or hostility : altercation ; also : a rough argument or fight : scuffle