also: うみくさ · うみぐさ
noun
marine plant; seagrass
Botanical term for flowering plants that live in marine environments, distinct from algae (海藻).
海草は海底に根を張って育つ。
Seagrass grows by putting down roots on the seabed.
この湾には多様な海草が生息している。
Various marine plants inhabit this bay.
noun
Colloquial use; in everyday speech, 海草 often refers to seaweed in general, though botanically 海藻 is more precise.
See also: 海藻
海岸に海草がたくさん打ち上げられていた。
A lot of seaweed had washed up on the shore.
Rare kun'yomi reading; may appear in older or poetic contexts.
Rare voiced variant of うみくさ; not commonly used.
海藻 refers specifically to algae (seaweed), while 海草 in its strict sense means seagrass (a flowering plant). In casual use, 海草 is often used interchangeably with 海藻.
Compound of 海 (sea) and 草 (grass/plant). The reading かいそう is the standard on'yomi. The kun'yomi readings うみくさ and うみぐさ are rare and likely older or dialectal.