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slang An abbreviated spelling of "baby" typically used in text messages or online communication. Almost always written in lower case. Aw, what's wrong, bb? A: "Look at this precious bb!" B: "OMG that's the cutest kitten I've ever seen."
A stupid person. (A "BB" is a very small pellet used as ammunition.) Did you see the guy who's wearing two different shoes? What a BB brain.
n. a stupid person; a person seemingly with a brain the size of buckshot. (Also a rude term of address.) What BB brain left the door open?