noun
Technical term in marine biology for aquatic animals that swim actively, as opposed to plankton.
遊泳動物には魚類やイカ、クジラなどが含まれる。
Nekton includes fish, squid, whales, and the like.
Plankton are drifting organisms, while 遊泳動物 (nekton) are strong swimmers.
Compound of 遊泳 (swimming) and 動物 (animal), a calque of the English 'nekton'.