frogbit vs water plant

frogbit and water plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
frogbit	Yes	No	No	No
water plant	Yes	No	No	No

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

frogbit: European floating plant with roundish heart-shaped leaves and white flowers
water 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 frogbit include aquatic plant, hydrophyte, hydrophytic plant.

frogbit (noun)	water plant (noun)
European floating plant with roundish heart-shaped leaves and white flowers	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