# decomposition

/ˌdikəmpəˈzɪʃən/ (US) · /dˌiːkɒmpəzˈɪʃən/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/decomposition
Updated: 2026-05-07

## Definition

the natural process of dead plants or animals breaking down and rotting. It is how nature recycles nutrients back into the soil.

For teachers: the biological and chemical process by which organic substances are broken down into simpler matter. Often involves the action of bacteria or fungi and is essential for nutrient cycling in ecosystems.

## Examples

- The decomposition of leaves provides nutrients for the forest floor.
- Scientists studied the rate of decomposition in the swamp to understand how carbon is stored in the mud.
- In forensic science, the specific stages of decomposition can provide investigators with a reliable timeline for estimating the interval since a biological organism ceased to function.

## Usage notes

- Primarily uncountable when referring to the general process; can be countable in technical contexts referring to specific chemical breakdowns.

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