tape grass vs hydrophyte

tape grass and hydrophyte both are nouns.

Word	Noun	Adjective	Verb	Adverb
tape grass	Yes	No	No	No
hydrophyte	Yes	No	No	No

As nouns, hydrophyte is a hypernym of tape grass; that is, hydrophyte is a word with a broader meaning than tape grass:

tape grass: submerged aquatic plant with ribbonlike leaves; Old World and Australia
hydrophyte: 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 tape grass include aquatic plant, hydrophytic plant, water plant.

tape grass (noun)	hydrophyte (noun)
submerged aquatic plant with ribbonlike leaves; Old World and Australia	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