n. (Chem.) a morphine derivative, diacetyl morphine, used to relieve severe pain and as a sedative. It is highly addictive, and its use is strictly controlled in the U.S. by federal law. It is a popular strong narcotic drug of abuse, in part because it is more soluble than morphine. It is sometimes included as one of the components of Brompton's mixture, used to control pain in terminallly ill patients.
Syn. -- diacetyl morphine, H, horse, junk, scag, shit, smack. [ WordNet 1.5 +PJC ]

n. [ F. héroïne, L. heroina, Gr. &unr_;, fem. of &unr_;. See Hero. ] 1. A woman of an heroic spirit. [ 1913 Webster ]

The heroine assumed the woman's place. Dryden. [ 1913 Webster ]

2. The principal female person who figures in a remarkable action, or as the subject of a poem or story. [ 1913 Webster ]