brain·​box | \ ˈbrān-ˌbäks How to pronounce brainbox (audio) \
variants: or brain box
plural brainboxes or brain boxes

Definition of brainbox

1a : cranium, braincase Your brain box is about to whack the pavement—hard!Consumer Reports, July/August 1996
b : mind, brain And why did everyone insist on reminding him of his ex-wife? Because all it did was bring her right back into his head again, back into the old brainbox, where she'd always done the most damage.— Robert McCarthy, Zoetrope: All-Story, Spring 2005
2 chiefly British : a very intelligent person I was good at school; I was a total brain box. At a small town school, being brainy was not necessarily an asset.— Karine Polwart, quoted in The (London) Times Educational Supplement, 15 Feb. 2013

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First Known Use of brainbox

1789, in the meaning defined at sense 1a

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The first known use of brainbox was in 1789

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Dictionary Entries Near brainbox

brain attack


brain candy

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Cite this Entry

“Brainbox.” Dictionary, Merriam-Webster, Accessed 20 May. 2022.

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