boo-boo face n. a pout or pouty facial expression; moue; boo-boo lip, an out-thrust lip. Editorial Note: Probably from the facial expression children make when they have a boo-boo ‘minor injury.’ (source: Double-Tongued Dictionary)
Further reading
One secret to writing well is … there is no secret! There’s no substitute for simply sitting down day after day to practice the craft and learn from your mistakes. Plus, childhood mixups around word definitions can lead to some funny stories...
It’s hard to imagine now, but there was a time when people disagreed over the best word to use when answering the phone. Alexander Graham Bell suggested answering with ahoy! but Thomas Edison was partial to hello! A fascinating new book about...
actually…its more of a i smell boo-boo face. you know like you just smelt crap. i.e boo-boo.