heroin

noun

her·​o·​in ˈher-ə-wən How to pronounce heroin (audio)
ˈhe-rə-
: a strongly physiologically addictive narcotic C21H23NO5 that is made by acetylation of but is more potent than morphine and that is prohibited for medical use in the U.S. but is used illicitly for its euphoric effects
heroinism noun

Examples of heroin in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Jenkins also admitted stealing cocaine, heroin, and marijuana—along with pharmaceuticals looted during the unrest following the death of Freddie Gray in 2015. Mike Hellgren, CBS News, 7 May 2026 That day, Beverley purchased a supply of heroin for her son, fearful that he would be arrested during the purchase, PEOPLE reported in 1996. Nicole Briese, PEOPLE, 6 May 2026 Drug dealers mix fentanyl, because of its potency and low cost, with other drugs including heroin, methamphetamine and cocaine, which increases the likelihood of a fatal dose, according to the DEA. Rosalio Ahumada, Sacbee.com, 6 May 2026 Lopez-Sanchez was a member of a group distributing methamphetamine, heroin and cocaine, according to the news release. Eleanor Nash, Kansas City Star, 6 May 2026 See All Example Sentences for heroin

Word History

Etymology

from Heroin, a trademark

First Known Use

1898, in the meaning defined above

Time Traveler
The first known use of heroin was in 1898

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Cite this Entry

“Heroin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heroin. Accessed 15 May. 2026.

Kids Definition

heroin

noun
her·​o·​in ˈher-ə-wən How to pronounce heroin (audio)
: a strongly addictive drug made from the opium poppy and stronger than morphine

Medical Definition

heroin

noun
her·​o·​in ˈher-ə-wən How to pronounce heroin (audio)
: a strongly physiologically addictive narcotic C21H23NO5 that is made by acetylation of but is more potent than morphine and that is prohibited for medical use in the United States but is used illicitly for its euphoric effects

called also acetomorphine, diacetylmorphine, diamorphine

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