|tectonic boundary where two plates are moving toward each other|
|central portion of the earth believed to be composed mainly of iron and nickel in a molten state|
|—n , pl -mas, -mata|
|1.||a paste or suspension consisting of a finely divided solid dispersed in a liquid|
|2.||hot molten rock, usually formed in the earth's upper mantle, some of which finds its way into the crust and onto the earth's surface, where it solidifies to form igneous rock|
|[C15, from Latin: dregs (of an ointment), from Greek: salve made by kneading, from massein to knead]|
magma mag·ma (māg'mə)
A mixture of finely divided solids with enough liquid to produce a pasty mass.
A suspension of particles in a liquid, such as milk of magnesia.
|magma (māg'mə) Pronunciation Key
Plural magmata (māg-mä'tə) or magmas
The molten rock material that originates under the Earth's crust and forms igneous rock when it has cooled. When magma cools and solidifies beneath the Earth's surface, it forms what are known as intrusive rocks. When it reaches the Earth's surface, it flows out as lava and forms extrusive (or volcanic) rocks.