blue-green alga


plural blue-green algae also blue-green algas

Example Sentences

Recent Examples on the Web The algae partner can be either a green alga or a blue-green alga, known as cyanobacteria. Howard Garrett, Dallas News, 17 June 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'blue-green alga.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1880, in the meaning defined above

Time Traveler
The first known use of blue-green alga was in 1880

Dictionary Entries Near blue-green alga

Cite this Entry

“Blue-green alga.” Dictionary, Merriam-Webster, Accessed 3 Feb. 2023.

Kids Definition

blue-green alga

: any of a major group of microorganisms that typically live in water and undergo photosynthesis and that are now usually classified as bacteria or sometimes as plants

called also cyanobacterium

Medical Definition

blue-green alga

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