Diatomaceous earth

Pronunciation
/dye-ah-to-may-shus urth/
Category
Insecticide
Singular
Diatomaceous earth
Plural
Diatomaceous earths

Definition

A soft, naturally occurring sedimentary rock composed of fossilized diatoms, a type of algae. When ground into a fine powder, it is used as an insecticide and desiccant.

Etymology

From Greek 'diatoma' meaning 'cut in half,' referring to the shape of diatom shells, and 'earth'.

Example

Diatomaceous earth is used to control pests in stored grain.

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