any fern of the very large genus Asplenium, of worldwide distribution. Some, esp the bird's nest fern (A. nidus), are grown as greenhouse or house plants for their decorative evergreen fronds: family Polypodiaceae
See also spleenwort
Word origin
New Latin, from Latin asplēnum, from Greek asplēnon spleenwort, from a- not + splēn spleen (from its reputed medicinal properties)