# porosity

/pɔːɹˈɒsɪti/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/porosity
Updated: 2026-05-31

## Definition

the amount of small holes or spaces in a material. These holes can let air, water, or other liquids pass through.

For teachers: the quality or state of being porous; the presence of numerous small openings or interstices in a substance. Often measured as the ratio of void volume to total volume.

## Examples

- The high porosity of the soil allows water to drain quickly.
- Engineers must account for the porosity of the concrete when designing structures that will be exposed to heavy rain.
- The unique porosity of the volcanic rock allows it to act as a natural filter, removing impurities from groundwater as it passes through the layers.

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