Definition - What does Magma mean?
Magma is the name given to the semi-molten material that lies beneath or within the earth's crust and forms into igneous rocks as it cools into solid material. Magma sits at extremely hot temperatures, where rock can move from solid material to a liquid. The definition extends to any material which is party composed of solid and liquid material, thus the defining feature of magma is this mixture.
Safeopedia explains Magma
Magma that is found under or in the earth's crust and is seen in volcanic activity is made partially of molten rock, but contains some suspended solids like crystals, which may have a higher melting point. The cooler parts of the outside of magma may also cool and solidify. Earth's magma has many purposes including helping warm our planet, forming land masses and igneous rocks, and releasing pressure.