Consisting of or making up a large mass; bulky, heavy, and solid: a massive piece of furniture. Large or imposing, as in quantity, scope, degree, intensity, or scale: "Local defense must be reinforced by the further deterrent of massive retaliatory power\u201d ( John Foster Dulles). See Synonyms at heavy. Large in comparison with the usual amount: a massive dose of a drug. Pathology Affecting a large area of bodily tissue; widespread and severe: massive gangrene. Mineralogy Lacking internal crystalline structure; amorphous. Geology Without internal structure or layers and homogeneous in composition. Used of a rock.