| dryopteridaceae | (n) alternative names for one of a number of families into which the family Polypodiaceae has been subdivided in some classification systems, Syn. Athyriaceae, family Dryopteridaceae, family Athyriaceae |
| pteridaceae | (n) one of a number of families into which the family Polypodiaceae has been subdivided in some classification systems; Pteridaceae is itself in turn sometimes further subdivided, Syn. family Pteridaceae |
| thelypteridaceae | (n) genera Thelypteris, Phegopteris, and others, Syn. family Thelypteridaceae |