WordNet (r) 3.0 (2006):

silvery spleenwort
    n 1: fern with elongate silvery outgrowths enclosing the
         developing spores [syn: silvery spleenwort, Deparia
         acrostichoides, Athyrium thelypteroides]
    2: North American fern with narrow fronds on yellowish
       leafstalks [syn: silvery spleenwort, glade fern, narrow-
       leaved spleenwort, Athyrium pycnocarpon, Diplazium
       pycnocarpon]