| Noun | 1. | genus Gymnocarpium - oak ferns: in some classification systems included in genus Thelypteris fern genus - genera of ferns and fern allies Athyriaceae, Dryopteridaceae, family Athyriaceae, family Dryopteridaceae - alternative names for one of a number of families into which the family Polypodiaceae has been subdivided in some classification systems Gymnocarpium dryopteris, oak fern, Thelypteris dryopteris - bright blue-green fern widely distributed especially in damp acid woodlands of temperate northern hemisphere |