fern vs fern seed

fern and fern seed both are nouns.

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

fern (noun)	fern seed (noun)
any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores	the asexual spore of ferns that resembles dust; once thought to be seeds and to make the possessor invisible