The Collaborative International Dictionary
Pteridology
Pteridology \Pter`i*dol"o*gy\, n. [Gr. ?, ?, a fern + -logy.] That department of botany which treats of ferns.
Wiktionary
pteridology
n. (context botany English) The scientific study of ferns and other pteridophytes.
WordNet
pteridology
n. the branch of botany that studies ferns