cy·​a·​no·​bac·​te·​ri·​um | \ˌsī-ə-nō-bak-ˈtir-ē-əm, sī-ˌa-nō-\

Definition of cyanobacterium 

: any of a major group (Cyanobacteria) of photosynthetic bacteria that are single-celled but often form colonies in the form of filaments, sheets, or spheres and are found in diverse environments (such as salt and fresh water, soils, and on rocks)

Note: Like other bacteria, cyanobacteria lack a nuclear membrane and membrane-bound organelles and have cell walls containing peptidoglycan. However, cyanobacteria were more commonly grouped with algae in the past because they possess a type of chlorophyll (chlorophyll a) not found in other bacteria and because they produce oxygen as a by-product of photosynthesis.

called also blue-green alga

Other Words from cyanobacterium

cyanobacterial \ˌsī-​ə-​nō-​bak-​ˈtir-​ē-​əl, sī-​ˌa-​nō-​ \ adjective

First Known Use of cyanobacterium

1974, in the meaning defined above

History and Etymology for cyanobacterium

New Latin

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cy·​a·​no·​bac·​te·​ri·​um | \-bak-ˈtir-ē-əm \
plural cyanobacteria\-​ē-​ə \

Medical Definition of cyanobacterium 

: any of a major group (Cyanobacteria) of photosynthetic bacteria that produce molecular oxygen and use water as an electron-donating substrate in photosynthesis

called also blue-green alga

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a nest or breeding place

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