The definition of boo is a way to show disapproval, or to scare or surprise someone.(interjection)
To boo is to make a sound of disapproval.(verb)
An example of boo is what a crowd does to show their dislike of what a speaker says.
Boo is defined as a term of endearment for a boyfriend or girlfriend, a sound make to show disapproval of something that was said, or is slang for marijuana.(noun)
See boo in Webster's New World College Dictionary
See boo in American Heritage Dictionary 4
noun pl. boos boos
Origin: Origin unknown.
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