An ocean current; a large flow of seawater such as the Kuroshio, which affects climate and fishing grounds.
黒潮は日本沿岸に大きな影響を与える海流だ。
The Kuroshio is an ocean current that greatly affects the coasts of Japan.
海流の速さと方向は船の航行に重要だ。
The speed and direction of ocean currents are important for ship navigation.
海流に乗ってゴミや漂流物が移動することがある。
Trash and drift objects can move along with ocean currents.