Geology Word of the Week: M is for Magma

Glowing lava in Hawaii. Image taken from Wikipedia Commons here.

def. Magma
1. Molten (liquid) rock below the Earth's surface. Often contains volatiles, crystals, and small fragments of solid rock.
2. Not a synonym for lava, which is what you call magma after it has been erupted or extruded onto the Earth's surface.
3. A favorite word of evil scientists, at least in Hollywood movies.