# silt

/ˈsɪɫt/ (US) · /sˈɪlt/ (UK)

Source: https://englishreference.com/word/silt
Updated: 2026-08-27

## Senses

### 1. fine sediment

noun · CEFR B2 · Technical

very fine sand or earth that water carries and leaves behind as mud at the bottom of a river.

For teachers: fine-grained sediment, typically ranging from 0.002 to 0.06 mm in diameter, deposited by moving water. Uncountable in general use.

- The river was brown and thick with silt after the heavy summer rain.
- The delta is formed by the gradual accumulation of silt carried downstream by the river over thousands of years.

### 2. to fill with mud

verb · CEFR C1 · Technical

to become blocked or filled with fine mud or sand.

For teachers: to become choked or obstructed with silt; often used with the particle 'up'.

- The harbour started to silt up because the water was moving too slowly.
- Without regular dredging, the canal will eventually silt up and become impassable for larger commercial vessels.

Usage: Often used as the phrasal verb 'silt up'.

## Examples

- The river is full of silt after the heavy rain.
- Farmers often worry about silt building up in their irrigation channels because it can clog the pipes.
- The delta's fertile soil is largely composed of silt, which is carried downstream by the river and settles in the shallower waters before the current slows.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.