Source : Webster's Revised Unabridged Dictionary (1913)

Maidenhair \Maid"en*hair`\, n. (Bot.)
   A fern of the genus {Adiantum} ({A. pedatum}), having very
   slender graceful stalks. It is common in the United States,
   and is sometimes used in medicine. The name is also applied
   to other species of the same genus, as to the Venus-hair.

   {Maiden grass}, the smaller quaking grass.

   {Maiden tree}. See {Ginkgo}.

Source : WordNet®

maidenhair
     n : any of various small to large terrestrial ferns of the genus
         Adiantum having delicate palmately branched fronds [syn:
         {maidenhair fern}]