Entry 2 senses Webster, 1913 boo-boo · IPA /ˈbuːˌbuː/ 01 n. an embarrassing mistake. 1. an embarrassing mistake. 2. a minor injury, such as an abrasion on the skin; -- child's talk. Syn. blunder, blooper, bungle, foul-up, flub, botch, boner, misdoing.