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crackbrain

noun crack·brain \-ˌbrān\

Definition of CRACKBRAIN

:  an erratic person :  crackpot
— crack·brained \-ˈbrānd\ adjective
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First Known Use of CRACKBRAIN

circa 1570

Related to CRACKBRAIN

Synonyms
bug, lunatic, crazy, fool, fruitcake, head case, loon, loony, maniac, nut, nutcase, nutter [British slang], psycho, psychopath, sickie, sicko, wacko (also whacko)

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