diatom

noun di·a·tom \ˈdī-ə-ˌtäm\

Definition of DIATOM

: any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomaceous earth

See diatom defined for kids

ultimately from Greek diatomos cut in half, from diatemnein to cut through, from dia- + temnein to cut — more at tome

First Known Use: 1845

Medical Dictionary

noun di·a·tom \ˈdī-ə-ˌtäm\

: any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomite

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