Pteridium aquilinum vs fern

Pteridium aquilinum and fern both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pteridium aquilinum	Yes	No	No	No
fern	Yes	No	No	No

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

Pteridium aquilinum: large coarse fern often several feet high; essentially weed ferns; cosmopolitan
fern: any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores

Pteridium aquilinum (noun)	fern (noun)
large coarse fern often several feet high; essentially weed ferns; cosmopolitan	any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores