(1):

(n.) The amorphous or homogenous matrix or ground mass, as distinguished from well-defined crystals; as, the magma of porphyry.

(2):

(n.) A thick residuum obtained from certain substances after the fluid parts are expressed from them; the grounds which remain after treating a substance with any menstruum, as water or alcohol.

(3):

(n.) Any crude mixture of mineral or organic matters in the state of a thin paste.

(4):

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

(5):

(n.) The glassy base of an eruptive rock.

(6):

(n.) A salve or confection of thick consistency.