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The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.

Morphina- m. Acetate of, morphinae acetas- m. and Zinc, double iodide of, Zinc and Morphia, double iodide of, - m. Citrateof, see Morphina- m. Muriate of, see Morphina- m. Sulphate of, Morphinae sulphas.

n. [French] A vegetable alkaloid extracted from opium. Its salts are much used in medicine as an anodyne.