Igneous (adjective)

1. Of, relating to, or formed by fire or heat; volcanic.
2. Of, relating to, or formed by solidification of molten magma or lava.

Origin:

Late 18th century: from latin igneus, from ignis "fire".

Examples:

1. The island was formed from igneous rock.
2. Igneous rocks are formed by the solidification of molten magma or lava.
3. The igneous rocks in the area around the volcano were formed by volcanic activity.
4. Igneous rocks are the most abundant rocks on Earth's surface.
5. The igneous rock granite is composed mainly of quartz, feldspar and mica.