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
ˈher-ə-wə-ˌni-zəm How to pronounce heroin (audio)
ˈhe-rə-
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.
While taking him into custody, cops allegedly found cocaine, heroin, drug paraphernalia and $2,7000 cash inside his car. — Kerry Burke, New York Daily News, 9 Aug. 2026 Irish police said at the time that the ⁠gang had ‌gone from dealing heroin and cocaine in Dublin in the 1990s to operating across Europe. — CNN Money, 9 Aug. 2026 Bourdain was open about his struggles with using heroin in his life, and Leo is the one that introduces him to the heroin dealer in Provincetown. — Matt Minton, Variety, 8 Aug. 2026 Not this again, survivors of heroin chic and low-rise denim beg. — Lauren Michele Jackson, New Yorker, 8 Aug. 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

Rhymes for heroin

See All Rhymes for heroin

Browse Nearby Words

heroic verse
heroin
heroine
See all Nearby Words

Cite this Entry

“Heroin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heroin. Accessed 19 Aug. 2026.

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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

More from Merriam-Webster on heroin

Nglish: Translation of heroin for Spanish Speakers

Britannica.com: Encyclopedia article about heroin

Last Updated: - Updated example sentences
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