progymnosperm vs gymnosperm

progymnosperm and gymnosperm both are nouns.

Word	Noun	Adjective	Verb	Adverb
progymnosperm	Yes	No	No	No
gymnosperm	Yes	No	No	No

As nouns, gymnosperm is a hypernym of progymnosperm; that is, gymnosperm is a word with a broader meaning than progymnosperm:

progymnosperm: an ancestral fossil type from which modern gymnosperms are thought to have derived
gymnosperm: plants of the class Gymnospermae having seeds not enclosed in an ovary

progymnosperm (noun)	gymnosperm (noun)
an ancestral fossil type from which modern gymnosperms are thought to have derived	plants of the class Gymnospermae having seeds not enclosed in an ovary