WordNet (r) 3.0 (2006):

Blechnaceae
    n 1: one of a number of families into which the family
         Polypodiaceae has been subdivided in some classification
         systems; includes genera Blechnum, Doodia, Sadleria,
         Stenochlaena, and Woodwardia [syn: Blechnaceae, family
         Blechnaceae]