water starwort vs aquatic plant

water starwort and aquatic plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
water starwort	Yes	No	No	No
aquatic plant	Yes	No	No	No

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

water starwort: any of several aquatic plants having a star-shaped rosette of floating leaves; America, Europe and Asia
aquatic plant: a plant that grows partly or wholly in water whether rooted in the mud, as a lotus, or floating without anchorage, as the water hyacinth

Other hypernyms of water starwort include hydrophyte, hydrophytic plant, water plant.

water starwort (noun)	aquatic plant (noun)
any of several aquatic plants having a star-shaped rosette of floating leaves; America, Europe and Asia	a plant that grows partly or wholly in water whether rooted in the mud, as a lotus, or floating without anchorage, as the water hyacinth