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• cyanobacteria
  cyanobacteria

  plural noun

  a widely distributed group of photosynthetic bacteria, occurring singly or in colonies in terrestrial and aquatic habitats: often mistakenly referred to as algae, especially when called by their most common misnomer, blue-green algae .
• Cyanobacteria
  Cyanobacteria

  noun

  the phylum, or subkingdom, that comprises the cyanobacteria.

cyanobacteria

¹ American  

[sahy-uh-noh-bak-teer-ee-uh, sahy-an-oh-] / ˌsaɪ ə noʊ bækˈtɪər i ə, saɪˌæn oʊ- /

plural noun

singular

cyanobacterium

1. Microbiology. a widely distributed group of photosynthetic bacteria, occurring singly or in colonies in terrestrial and aquatic habitats: often mistakenly referred to as algae, especially when called by their most common misnomer, blue-green algae .

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Cyanobacteria ² American  

[sahy-uh-noh-bak-teer-ee-uh, sahy-an-oh-] / ˌsaɪ ə noʊ bækˈtɪər i ə, saɪˌæn oʊ- /

noun

Microbiology.

1. the phylum, or subkingdom, that comprises the cyanobacteria.

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cyanobacteria British  

/ ˌsaɪənəʊbækˈtɪərɪə /

plural noun

1. Former name: blue-green algae.  a group of photosynthetic bacteria (phylum Cyanobacteria ) containing a blue photosynthetic pigment

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Etymology

Origin of cyanobacteria¹

First recorded in 1975–80; cyano- ¹ + bacteria

Origin of Cyanobacteria²

See cyanobacteria ( def. )

Example Sentences

Among them, cyanobacteria stand out for producing the oxygen that filled our atmosphere and allowed complex life to emerge.

From Science Daily • Apr. 20, 2026

He found that Anabaena and some related cyanobacteria contain a system known as ParMR encoded within their chromosomes.

From Science Daily • Apr. 20, 2026

Previous studies helped establish that cyanobacteria began producing oxygen around 2.9 billion years ago, while oxygen did not permanently accumulate in the atmosphere until roughly 2.33 billion years ago during the Great Oxidation Event.

From Science Daily • Feb. 18, 2026

The beauty of the sky contrasts sharply with the water, sometimes blue, but often a murky green from cyanobacteria or stained black.

From BBC • Jan. 29, 2026

Production of GlcHMS326 increases significantly when the cyanobacteria are exposed to UV-A, UV-B, and high salt conditions.

From Science Daily • Jan. 13, 2026