spleenwort vs fern

spleenwort and fern both are nouns.

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

As nouns, fern is a hypernym of spleenwort; that is, fern is a word with a broader meaning than spleenwort:

spleenwort: any of various chiefly rock-inhabiting ferns of the genus Asplenium
fern: any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores

spleenwort (noun)	fern (noun)
any of various chiefly rock-inhabiting ferns of the genus Asplenium	any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores