Definition of diatom in English:


Pronunciation /ˈdīəˌtäm/ /ˈdaɪəˌtɑm/

Translate diatom into Spanish


  • A single-celled alga which has a cell wall of silica. Many kinds are planktonic, and extensive fossil deposits have been found.

    Class Bacillariophyceae, division Chromophycota or Heterokontophyta (or phylum Bacillariophyta, kingdom Protista)

    ‘From single-celled algae called diatoms to the story of a man who plants acorns, IDFuel reminds us that inspiration for design is all around us.’
    • ‘The slime molds are now known to be a mixture of three or four unrelated groups, and the oomycetes are now classified in the Chromista, with the diatoms and brown algae.’
    • ‘Algae, diatoms, dinoflagellates, and photosynthetic bacteria all belong to this group of organisms.’
    • ‘Many are planktonic like the diatoms and Sargassum, floating free near the water surface, and being carried along by the surface currents.’
    • ‘For example, replacement of diatoms with chlorophytes will alter cycling of silica because diatoms require silica and chlorophytes do not.’


Mid 19th century from modern Latin Diatoma (genus name), from Greek diatomos ‘cut in two’, from diatemnein ‘to cut through’.