The Collaborative International Dictionary of English v.0.48:

Beldam \Bel"dam\ Beldame \Bel"dame\, n. [Pref. bel-, denoting
   relationship + dame mother: cf. F. belledame fair lady, It.
   belladonna. See Belle, and Dame.]
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   1. Grandmother; -- corresponding to belsire.
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            To show the beldam daughters of her daughter.
                                                  --Shak.
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   2. An old woman in general; especially, an ugly old woman; a
      hag.

   Syn: hag, beldam, witch, crone.
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              Around the beldam all erect they hang. --Akenside.
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