diatom
/ˈdʌɪətəm
/noun Biology
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).
- 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.
Derivatives
diatomaceous
/ adjective ...- Although diatoms are universal in fresh and sea water, they achieve greater importance in high-latitude oceanic areas, as well as in some continental margin basins where they form diatomaceous ooze.
- Massive, bioturbated terrigenous silty clay and diatomaceous mud dominate sedimentation in the distal ice-shelf environment.
- ‘The bottom appeared light and clear, a waste of firm diatomaceous [algae-skeleton] ooze,’ said Piccard.
Origin
Mid 19th century: from modern Latin Diatoma (genus name), from Greek diatomos 'cut in two', from diatemnein 'to cut through'.