sediment

American  

[sed-uh-muhnt, sed-uh-ment] / ˈsɛd ə mənt, ˈsɛd əˌmɛnt /

noun

1. the matter that settles to the bottom of a liquid; lees; dregs.

2. Geology. mineral or organic matter deposited by water, air, or ice.

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verb (used with object)

1. to deposit as sediment.

verb (used without object)

1. to form or deposit sediment.

sediment British  

/ ˌsɛdɪˈmɛntəs, ˈsɛdɪmənt /

noun

1. matter that settles to the bottom of a liquid

2. material that has been deposited from water, ice, or wind

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sediment Scientific  

/ sĕd′ə-mənt /

1. Geology Solid fragmented material, such as silt, sand, gravel, chemical precipitates, and fossil fragments, that is transported and deposited by water, ice, or wind or that accumulates through chemical precipitation or secretion by organisms, and that forms layers on the Earth's surface. Sedimentary rocks consist of consolidated sediment.

2. Particles of solid matter that settle out of a suspension to the bottom of the liquid.

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Other Word Forms

• sedimentous adjective
• self-sedimented adjective

Etymology

Origin of sediment

1540–50; < Latin sedimentum, equivalent to sedi- (combining form of sedēre to sit ¹, settle) + -mentum -ment

Explanation

Sediment is the accumulation of sand and dirt that settles in the bottom of lakes. Sediment is also what you get in the bottom of a glass of iced tea when the sugar doesn’t all dissolve. The noun sediment comes from the Latin word sedere, meaning “to settle,” or “sit.” Sediment is the little bits of solids that sink to the bottom of a container of liquid, whether that container is a body of water or a holding tank at a sewage treatment plant. Millions of years ago, lakes dried up and glaciers compressed their sediment. In this sedimentary rock, fossils are found, giving us clues about prehistoric life.

Example Sentences

Citizen scientists will then be encouraged to gather sediment from rooftops and gutters and use magnets, sieves, and microscopes provided by the project to isolate potential micrometeorites.

From BBC • Apr. 4, 2026

These structures form when communities of microbes grow across sediment, leaving behind distinctive patterns.

From Science Daily • Apr. 3, 2026

In addition, they are prevalent throughout the environment — in alpine snow, deep sea sediment and drinking water.

From Los Angeles Times • Apr. 2, 2026

The water that poured out of the lake picked up stones, sand and other sediment as it flowed through the rocky mountain channels, triggering a series of landslides along the way.

From The Wall Street Journal • Apr. 1, 2026

They dove thirty feet and then removed another three feet of sediment before uncovering one of the Hunley’s two small conning towers.

From "Shipwrecked!" by Martin W. Sandler

Related Words

• debris
• powder
• silt
• trash
• waste