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noun

algae

AL-gee
noun
1
Simple, mostly aquatic plant-like organisms that photosynthesize, ranging from single-celled forms to seaweed.
"Green algae covered the surface of the pond by midsummer."
"Some biofuels are produced by growing algae in large tanks."

How to Use Algae

Learner’s notes

In plain EnglishA broad group of simple water-dwelling organisms, from microscopic pond scum to giant kelp.

Common mistake

"Algae" is technically plural (the singular is "alga"), but in everyday use people usually treat it as a mass noun, like "moss" — "the algae is spreading" is common even though purists prefer "are".

Common pairings
algae bloom blue-green algae algae growth

Word Forms

algae plural, algaes plural

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Green _____ covered the surface of the pond by midsummer.

Rhymes for algae

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Definitions: FreeDict original editorial