algae
n. uncountable B2 Upper Intermediate US //ˈæɫdʒi// UK //ˈælɡiː// al·gae
n. simple plants that live in water and have no roots, stems, or leaves. You see them as green slime on rocks or in ponds.
n. simple, mostly aquatic photosynthetic organisms ranging from microscopic single cells to large seaweeds, lacking true roots, stems, or leaves.
Green algae grew on the old pond stones.
The clear lake water allowed sunlight to reach the bottom, helping the algae grow quickly.
Marine biologists study how rising ocean temperatures affect algae blooms, which can disrupt local ecosystems and oxygen levels.