The Collaborative International Dictionary of English v.0.48:

Emarginate \E*mar"gi*nate\, v. t. [L. emarginare; e out +
   marginare to furnish with a margin, fr. margo margin.]
   To take away the margin of. Emarginate

The Collaborative International Dictionary of English v.0.48:

Emarginate \E*mar"gi*nate\, Emarginated \E*mar"gi*na`ted\, a.
   1. Having the margin interrupted by a notch or shallow sinus.
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   2. (Bot.) Notched at the summit.
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   3. (Cryst.) Having the edges truncated.
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WordNet (r) 3.0 (2006):

emarginate
    adj 1: having a notched tip