# igneous

/ˈɪɡniəs/ (US) · /ˈɪɡniəs/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/igneous
Updated: 2026-05-25

## Definition

describing rock that was formed when hot, melted rock (magma) cooled and hardened. You use this to talk about rocks like granite or basalt.

For teachers: relating to or denoting rock formed by the cooling and solidification of molten magma or lava. Often used to distinguish these rocks from sedimentary or metamorphic types.

## Examples

- Granite is a common type of igneous rock.
- The geologist identified the sample as an igneous rock because it had a rough, crystalline texture formed by slow cooling.
- Igneous formations often provide a chronological record of a region's volcanic history, as the chemical composition of the magma can indicate the depth and pressure of its origin.

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