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heroin

American  
[her-oh-in] / ˈhɛr oʊ ɪn /

noun

Pharmacology.

  1. a white, crystalline, narcotic powder, C 21 H 23 NO 5 , 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.

heroin British  
/ ˈhɛrəʊɪn /

noun

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

"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
heroin Scientific  
/ hĕr′ō-ĭn /

  1. A white, odorless, bitter crystalline compound, C 17 H 17 NO(C 2 H 3 O 2) 2, that is derived from morphine and is a highly addictive narcotic.

Etymology

Origin of heroin

1895–1900; formerly trademark; < German Heroin < Greek hērō-, stem of hḗrōs hero + German -in -in 2; allegedly so called from the feelings of power and euphoria which it stimulates

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Police found no drug paraphernalia, no traces of heroin in room 112, and nothing among Charmain's belongings.

From BBC • Apr. 11, 2026

They would grow to dominate not just the lucrative production of heroin and crystal meth, but the mineral and gold mines dotted around the state, as well as the avocado and lime industries.

From Los Angeles Times • Nov. 14, 2023

Border Patrol seizures represent a minority – between 13% and 19% – of the total weight of seizures at the border for cocaine, fentanyl, heroin and methamphetamine.

From Reuters • Aug. 9, 2023

As author and radio host Thom Hartmann sharply observed in a new essay, Fox News is like heroin to its public.

From Salon • Apr. 25, 2023

The cops grouped the boys together, lined them up against a fence, and demanded to know which of them had jettisoned the bag, which later turned out to be filled with quinine, not heroin.

From "The Color of Water: A Black Man's Tribute to His White Mother" by James McBride

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.