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.
Every person who finds a path away from fentanyl, heroin and other deadly drugs matters. — Chris Carroll, The Orlando Sentinel, 26 June 2026 Morgan died in his cell from an overdose caused by fentanyl and heroin, according to an autopsy. — Gavin J. Quinton, Los Angeles Times, 19 June 2026 Methamphetamine, heroin, cocaine, and pills can all contain a pencil‑tip amount capable of causing death. — Marvin Hurst, CBS News, 20 June 2026 Officers also searched the man’s vehicle and seized 13 grams of methamphetamine, 3 grams of heroin, multiple smoking pipes and syringes. — Reeti Malhotra, Sacbee.com, 25 June 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 7 Jul. 2026.

Copy Citation

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

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