sediment

Etymology

From Middle French sédiment, from Latin sedimentum < sedeō.

noun

1. A collection of small particles, particularly dirt, that precipitates from a river or other body of water.
   The Nile delta is composed of sediment that was washed down and deposited at the mouth of the river.

verb

1. (transitive) To deposit material as a sediment.
2. (intransitive) To be deposited as a sediment.