fern vs Filicopsida

fern and Filicopsida both are nouns.

Word	Noun	Adjective	Verb	Adverb
fern	Yes	No	No	No
Filicopsida	Yes	No	No	No

fern (noun)	Filicopsida (noun)
any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores	ferns