The Collaborative International Dictionary of English v.0.48:

Crownet \Crown"et\ (kroun"?t), n. [See Crown, Coronet.]
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   1. A coronet. [R.] --P. Whitehead.
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   2. The ultimate end and result of an undertaking; a chief
      end. [Obs.]
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            O this false soul of Egypt! this grave charm . . . .
            Whose bosom was my crownet, my chief end. --Shak.
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