The Collaborative International Dictionary of English v.0.48:

Brain \Brain\ (br[=a]n), v. t. [imp. & p. p. Brained
   (br[=a]nd); p. pr. & vb. n. Braining.]
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   1. To dash out the brains of; to kill by beating out the
      brains. Hence, Fig.: To destroy; to put an end to; to
      defeat.
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            There thou mayst brain him.           --Shak.
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            It was the swift celerity of the death . . .
            That brained my purpose.              --Shak.
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   2. To conceive; to understand. [Obs.]
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            'T is still a dream, or else such stuff as madmen
            Tongue, and brain not.                --Shak.
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