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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  
/ hĕrō-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.

See Examples For:

Janda's laboratory has previously developed vaccine candidates targeting both fentanyl and heroin.

From Science Daily Jun. 13, 2026

In the two weeks since the summit, news outlets have been dutifully publishing articles that draw on facts and medical expertise, explaining that Kennedy is wrong to compare people who use SSRIs to heroin addicts.

From Salon May 18, 2026

US President Donald Trump has made the fight against criminal gangs sending illicit drugs such as heroin, fentanyl, methamphetamines and cocaine one of his priorities.

From BBC Jan. 26, 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

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

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