pteridology vs phytology

pteridology and phytology both are nouns.

Word	Noun	Adjective	Verb	Adverb
pteridology	Yes	No	No	No
phytology	Yes	No	No	No

As nouns, phytology is a hypernym of pteridology; that is, phytology is a word with a broader meaning than pteridology:

Other hypernyms of pteridology include botany.

pteridology (noun)	phytology (noun)
the branch of botany that studies ferns	the branch of biology that studies plants