1) Aquatic plant 2) Eriocaulon aquaticum 3) Hydrophyte 4) Hydrophytic plant 5) Water plant 
• (n.) Any plant of a genus (Eriocaulon) of aquatic or marsh herbs with soft grass-like leaves.
Pipe'wort` noun (Botany) Any plant of a genus ( Eriocaulon ) of aquatic or marsh herbs with soft grass-like leaves. 
[n] - aquatic perennial of North America and Ireland and Hebrides having translucent green leaves in a basal spiral and dense buttonlike racemes of minute white flowers
Eriocaulon aquaticum noun aquatic perennial of North America and Ireland and Hebrides having translucent green leaves in a basal spiral and dense buttonlike racemes of minute white flowers