Igneous rock that solidified on surface following a volcanic eruption; extrusive rock or lava; generally cools quickly, therefore is fine grained.

See extrusive rock.

Igneous rocks derived from magma or magmatic materials that are poured out or ejected (extruded) at or very near the Earth's surface.

a crystalline or glassy igneous rock formed by volcanic action near the earth's surface. [AHDOS

Volcanic rock is an igneous rock of volcanic origin.