[ her-oh-in ]
/ ˈhɛr oʊ ɪn /

noun Pharmacology.

a white, crystalline, narcotic powder, C21H23NO5, derived from morphine, formerly used as an analgesic and sedative: manufacture and importation of heroin are now controlled by federal law in the U.S. because of the danger of addiction.

Origin of heroin

1895–1900; formerly trademark; < German Heroin < Greek hērō-, stem of hḗrōs hero + German -in -in2; allegedly so called from the feelings of power and euphoria which it stimulates

Can be confused

heroin heroine
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for heroin

British Dictionary definitions for heroin


/ (ˈhɛrəʊɪn) /


a white odourless bitter-tasting crystalline powder related to morphine: a highly addictive narcotic. Formula: C 21 H 23 NO 5Technical names: diamorphine, diacetylmorphine

Word Origin for heroin

C19: coined in German as a trademark, probably from hero, referring to its aggrandizing effect on the personality
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for heroin


[ hĕrō-ĭn ]


A white, bitter, crystalline compound that is derived from morphine and is a highly addictive narcotic.diacetylmorphine
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for heroin


[ hĕrō-ĭn ]

A white, odorless, bitter crystalline compound, C17H17NO(C2H3O2)2, that is derived from morphine and is a highly addictive narcotic.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.