plural noun
mi·​cro·​algae | \¦mīkrō+\

Definition of microalgae 

: algae (such as diatoms or chlorellas) not visible to the unaided eye

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Other Words from microalgae

microalgal \"+ \ adjective

First Known Use of microalgae

1869, in the meaning defined above

History and Etymology for microalgae

micr- + algae

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The first known use of microalgae was in 1869

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living or existing for a long time

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