- A soft, crumbly, porous sedimentary deposit formed from the fossil remains of diatoms.More example sentences
- Diatoms have an extensive fossil record going back to the Cretaceous; some rocks are formed almost entirely of fossil diatoms, and are known as diatomite or diatomaceous earth.
- The richest sources of diatom fossils are deposits of their skeletons known as diatomite, or diatomaceous earth.
- As the diatoms die, they sink to the ocean floor, becoming a thick ooze of decomposing matter, and eventually giving rise to deposits of the sediment called diatomaceous earth.
More definitions of diatomaceous earthDefinition of diatomaceous earth in:
- The US English dictionary