plural of magma

(geology) The molten matter within the earth, the source of the material of lava flows, dikes of eruptive rocks, etc.

plural of basaltic magma

Fluid rock material of basaltic origin

(geology) A large underground pool of molten rock lying under the surface of the earth's crust.

plural of magma chamber

plural of magmasphere

(geology, astronomy) A sphere of magma at the centre of a rocky planet or moon of sufficiently large size