noun
phytoplankton
Scientific term for microscopic plant-like organisms drifting in water; common in biology and environmental contexts.
植物プランクトンは海洋生態系の基礎です。
Phytoplankton are the foundation of the marine ecosystem.
Zooplankton, the animal counterpart; often mentioned together in ecological contexts.
Compound of 植物 (plant) and プランクトン (plankton), a direct calque of English 'phytoplankton'.