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.
Test strips are used to prevent unintentional consumption of fentanyl in drugs like cocaine, heroin and marijuana, which are sometimes laced with synthetic opioids. Bayliss Wagner, Austin American Statesman, 23 July 2025 In the heydays of the cocaine and heroin epidemics, drugs often traveled south along the I-95 corridor. Kate Cimini, Baltimore Sun, 12 July 2025 Ovidio Guzman Lopez, 35, admitted to running part of the Sinaloa Cartel, coordinating massive drug shipments, including fentanyl, heroin and cocaine into the U.S. and using violence to protect cartel operations, according to the U.S. Attorney's Office for the Northern District of Illinois. Stepheny Price, FOXNews.com, 12 July 2025 For the first time in the United Kingdom, people who inject illicit drugs such as heroin and cocaine can do so under medical supervision – in a safe environment and indoors. Olivia Kemp, CNN Money, 11 July 2025 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

Browse Nearby Words

Cite this Entry

“Heroin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heroin. Accessed 29 Jul. 2025.

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

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