silvery spleenwort vs narrow-leaved spleenwort

silvery spleenwort and narrow-leaved spleenwort both are nouns.

Word	Noun	Adjective	Verb	Adverb
silvery spleenwort	Yes	No	No	No
narrow-leaved spleenwort	Yes	No	No	No

As nouns, silvery spleenwort and narrow-leaved spleenwort are synonyms defined as:

silvery spleenwort and narrow-leaved spleenwort: North American fern with narrow fronds on yellowish leafstalks

Other synonyms of silvery spleenwort include Athyrium pycnocarpon, Diplazium pycnocarpon, glade fern.

silvery spleenwort (noun)	narrow-leaved spleenwort (noun)
North American fern with narrow fronds on yellowish leafstalks	North American fern with narrow fronds on yellowish leafstalks
fern with elongate silvery outgrowths enclosing the developing spores