blue-green algae

American  

[bloo-green al-jee] / ˈbluˌgrin ˈæl dʒi /

plural noun

Microbiology.

1. cyanobacteria.

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blue-green algae British  

plural noun

1. the former name for cyanobacteria

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Etymology

Origin of blue-green algae

First recorded in 1895–1900

Example Sentences

Last year, scientists in the country announced they had launched successful trials spraying the soil with cyanobacteria, also known as "blue-green algae" -- a method that helps retain moisture and facilitate tree rooting.

From Barron's • Dec. 18, 2025

During the warm months, Lake Erie becomes an ideal setting for cyanobacteria, also known as blue-green algae, to grow rapidly.

From Science Daily • Dec. 2, 2025

When this occurs, blue-green algae can form blooms that discolour the water, or produce floating mats or scums on the water's surface.

From BBC • Sep. 9, 2025

The blue-green algae, known as cyanobacteria, is a natural part of the ecosystem but can rapidly grow under certain conditions, including warm temperatures and calm water.

From Los Angeles Times • Aug. 29, 2024

For most of the four billion years since the origin of life, the dominant organisms were microscopic blue-green algae, which covered and filled the oceans.

From "Cosmos" by Carl Sagan