Grass; weeds; herbs — plants that grow close to the ground, such as turf or wild grass.
公園の草が伸びていたので、散歩道に入らないようにした。
The grass in the park had grown long, so I avoided going into the path.
朝露で草が濡れているから、座ると服が汚れるよ。
The grass is wet with morning dew, so if you sit you'll get your clothes dirty.
庭の草を刈るのは週末の仕事だ。
Mowing the grass in the yard is a weekend chore.
An archaic term referring to a hidden person or stealthy agent (ninja); rarely used in modern Japanese and mainly found in historical texts.
古い軍記物では『草』が隠密を指すことがあると記されている。
Old war chronicles record that 'kusa' can refer to covert agents.
Slang for marijuana or cannabis. This is colloquial and should be used carefully.
彼はパーティーで草を吸っているところを見られたらしい。
Apparently he was seen smoking weed at the party.
警察は草の所持で彼を逮捕した。
The police arrested him for possession of weed.
As a prefix, it indicates something unofficial, amateurish, or not genuine (e.g., 'kusayakyū' — amateur baseball).
草野球のチームに友達が入っている。
My friend has joined an amateur baseball team.
その大会は草大会なので、参加資格に制限はほとんどない。
That event is an amateur tournament, so there are few entry restrictions.
Internet slang used to express laughter (derived from repeated 'w' characters resembling grass). 'Kusa' = laugh/LOL. Used in casual online chats.
あの動画、本当に面白かった、草ｗｗｗ
That video was really funny — lol.
友達のミスにみんな『草』とコメントしている。
Everyone is commenting 'kusa' (lol) about our friend's mistake.
ネット掲示板では『ｗ』の代わりに『草』と書くことが多い。
On message boards people often write 'kusa' instead of 'w'.