遊ゆう泳えい生せい物ぶつゆうえいせいぶつMeanings1nounnektonTechnical term in marine biology for aquatic animals that can swim actively against currents, as opposed to plankton.遊ゆう泳えい生せい物ぶつには魚ぎょ類るいやイカ類るいが含ふくま