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A narcotic prepared from opium. morphia.

The principal and most active alkaloid of opium.

A natural alkaloid, C17H19NO3 + H2O, found in opium, occurring as a crystalline powder or in shining white or colorless prisms of bitter taste and no odor, almost insoluble in ether, very slightly soluble in chloroform and in cold water, somewhat soluble in boiling water, and more soluble in alcohol, especially boiling alcohol, becoming anhydrous and opaque at about 100 C., and melting at about 228 C. For its medicinal properties see under opium. List of poisons and their antidotes, see in appendix, page 940.