boos Definition

boo
exclamation, noun

boos
1. A sound expressing disapproval, or made when trying to frighten or surprise someone.

verb

tr & intr
booed, booing
1. To shout ‘boo' to express disapproval.

Example: The audience booed him off the stage

Idiom: he etc can't say boo to a goose (he etc couldn't say boo to a goose, he etc wouldn't say boo to a goose)

He etc is very shy or easily frightened.

Etymology: 19c.