silt

1 of 2

noun

ˈsilt 

1

: loose sedimentary material with rock particles usually ¹/₂₀ millimeter or less in diameter

also : soil containing 80 percent or more of such silt and less than 12 percent of clay

2

: a deposit of sediment (as by a river)

silty

ˈsil-tē 

adjective

silt

2 of 2

verb

silted; silting; silts

intransitive verb

: to become choked or obstructed with silt

—often used with up

the channel silted up

transitive verb

: to choke, fill, cover, or obstruct with silt or mud

siltation

sil-ˈtā-shən 

noun

Examples of silt in a Sentence

Verb

The entrance to the creek had silted shut.

Recent Examples on the Web

Noun

These silts were left behind when ancient river channels filled up or when floodwaters slowed down and gently dropped tiny particles. —Pranjal Malewar, New Atlas, 18 Oct. 2025

The latest fossils emerged from a layer of sandy silt just above an extraordinary trackway of hominin footprints made public last year. —Katie Hunt, CNN Money, 15 Oct. 2025

Verb

The rock was originally silt on the seafloor that, it's argued, hosted early microbial life that was buried by more silt, leaving the carbon as their remains. —Howard Lee, ArsTechnica, 11 Aug. 2025

Historically, the region itself was created by the natural flooding and silting processes of the Mississippi River, which flows across the breadth of the state before spilling into the Gulf of America. —David Blackmon, Forbes.com, 18 June 2025

Word History

Etymology

Noun

Middle English cylte, probably of Scandinavian origin; akin to Norwegian dialect sylt beach flooded at high tide; akin to Old High German sulza salt marsh, Old English sealt salt

First Known Use

Noun

15th century, in the meaning defined at sense 1

Verb

1799, in the meaning defined at intransitive sense

Rhymes for silt

• built
• gilt
• guilt
• hilt
• kilt
• lilt
• milt
• quilt
• spilt
• stilt
• tilt
• wilt

Kids Definition

silt

1 of 2 noun

ˈsilt 

1

: very small particles left as sediment from water

also : a soil made up mostly of silt with little clay

2

: a deposit of sediment (as by a river)

silty

ˈsil-tē 

adjective

silt

2 of 2 verb

: to make or become choked, blocked, filled, or covered with silt

the river channel silted up