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
noun
See boo in American Heritage Dictionary 4
noun pl. boos boos
Origin:
Origin: Imitative
.noun
Origin:
Origin: Origin unknown
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