The Collaborative International Dictionary of English v.0.48:

Microsorium \Microsorium\ prop. n.
   A genus of tropical usually epiphytic ferns, found from
   Africa to Asia, and from Polynesia to Australia.

   Syn: genus Microsorium.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Microsorium
    n 1: tropical usually epiphytic ferns; Africa to Asia and
         Polynesia to Australia [syn: Microsorium, genus
         Microsorium]