water sprite vs aquatic fern

water sprite and aquatic fern both are nouns.

Word	Noun	Adjective	Verb	Adverb
water sprite	Yes	No	No	No
aquatic fern	Yes	No	No	No

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

Other hypernyms of water sprite include water fern.

water sprite (noun)	aquatic fern (noun)
a fairy that inhabits water	ferns that grow in water
aquatic fern of tropical America often used in aquariums