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blue-green algae

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

plural noun

Microbiology.
  1. cyanobacteria.


blue-green algae British  

plural noun

  1. the former name for cyanobacteria

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of blue-green algae

First recorded in 1895–1900

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

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

Technically known as cyanobacteria, blue-green algae is a collection of microscopic organisms that are naturally present in lakes and streams.

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

Once the photosynthetic cells had appeared, very probably counterparts of today’s blue-green algae, the future respiratory mechanism of the earth was set in place.

From "The Lives of a Cell" by Lewis Thomas