Magmatism

[mag-muh] /ˈmæg mə/

noun, plural magmas, magmata
[mag-muh-tuh] /ˈmæg mə tə/ (Show IPA)
1.
Geology. molten material beneath or within the earth’s crust, from which igneous rock is formed.
2.
any crude mixture of finely divided mineral or organic matter.
3.
Chemistry, Pharmacology. a paste composed of solid and liquid matter.
/ˈmæɡmə/
noun (pl) -mas, -mata (-mətə)
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
n.

mid-15c., “dregs,” from Latin magma “dregs of an ointment,” from Greek magma “thick unguent, ointment,” from root of massein “to knead, mold,” from PIE *mag- “to knead” (see macerate). Geological meaning “molten rock” is 1859. Related: Magmalic.

magma mag·ma (māg’mə)
n.

magma
(māg’mə)
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.

Molten rock usually located deep within the mantle of the Earth that occasionally comes to the surface through cracks in the mantle or through the eruption of volcanoes.

Note: When magma cools and solidifies, it forms igneous rock, of which lava is one type.