What is the five-letter name for the molten rock that erupts from a volcano, forming lava when it cools?

Deep beneath the Earth's surface, tremendous heat and pressure cause solid rocks to melt, forming a superheated, viscous liquid. This molten material, often rich in dissolved gases, collects in chambers within the Earth's crust or upper mantle. Geologists refer to this underground reservoir of liquid rock as magma, a term derived from the Greek word for 'kneaded mixture' or 'thick ointment,' aptly describing its consistency.

When geological forces create pathways, this magma can begin to rise towards the surface. As it ascends, the pressure decreases, allowing some of the dissolved gases to expand, which can drive powerful volcanic eruptions. It's only once this molten rock breaches the Earth's surface and flows out of a volcano that its name changes.

Upon eruption, the now-exposed molten rock is called lava. The distinction is crucial: magma is the molten rock while it is still underground, whereas lava is the same material once it has emerged onto the surface. As lava cools, it solidifies and forms various types of igneous rocks, continually building up the volcanic landscape. The speed and manner of cooling greatly influence the rock's texture and crystal size, creating everything from glassy obsidian to coarse-grained basalt, a fundamental process that continually reshapes our planet's crust.