- Boob is defined as a slang term for breasts.
An example of boob is what a teenager might call a breast while looking at an underwear catalog.
- The definition of boob means an idiot or someone who is the brunt of a joke.
An example of a boob is a court jester.
boob definition by Webster's New World
Origin: ; from booby
Origin: probably ; from booby, baby talk for “breast”
boob definition by American Heritage Dictionary
Origin: Short for booby1.
noun Vulgar Slang
Origin: Short for booby2.