her·o·in | \ˈher-ə-wən, ˈhe-rə-\

Definition of heroin 

: 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

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Other Words from heroin

heroinism \ˈher-ə-wə-ˌni-zəm, ˈhe-rə- \ noun

Examples of heroin in a Sentence

Recent Examples on the Web

In Dennis’ case, (the heroin) was 100 percent fentanol. Donna Vickroy, Daily Southtown, "The Center's new commercial-grade kitchen to honor Homer Glen man who battled heroin addiction," 14 July 2018 Police searched the Hewins Street location and found about 600 grams of suspected heroin and cocaine, along with packaging material, Ryan’s office said. Danny Mcdonald, BostonGlobe.com, "Bust nets $200,000 worth of illegal drugs, Middlesex DA says," 13 July 2018 Opioid drugs — including pain pills, heroin and the heavy-duty painkiller fentanyl — have spawned the deadliest epidemic of drug overdoses in U.S. history. Washington Post, "‘It keeps us safe’: An NYC bathroom set up to stem overdoses," 13 July 2018 Ten years ago, my friend Lisa overdosed on heroin and died. Josie Duffy Rice, The Atlantic, "The Gospel According to Pusha T," 12 July 2018 For years now, the extent of the heroin and prescription opioid painkiller addiction scourge ravaging the United States has become increasingly clear. Sy Mukherjee, Fortune, "Brainstorm Health: Pain Patients and Opioids, Gene Editing Cholesterol, Doctor Burnout," 10 July 2018 The powder tested positive for heroin, according to court documents. Michael Williams Orlando Sentinel, star-telegram, "Super Bowl Giant busted with heroin after allegedly ramming cop car," 7 July 2018 The one-person trial had to be done overseas because the U.S. government classifies marijuana as a Schedule 1 drug, the same tier as heroin. Lizzie Johnson, SFChronicle.com, "Berkeley boy was ‘Patient X’ in first FDA-approved medicine derived from marijuana," 8 July 2018 During a four-hour period in 2017, 28 people in the town overdosed from heroin. Patrik Jonsson, The Christian Science Monitor, "As war vets enter the fray, stigma lessens around cannabis," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'heroin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of heroin

1898, in the meaning defined above

History and Etymology for heroin

from Heroin, a trademark

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Statistics for heroin

Last Updated

9 Oct 2018

Look-up Popularity

Time Traveler for heroin

The first known use of heroin was in 1898

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More Definitions for heroin



English Language Learners Definition of heroin

: a powerful illegal drug that is made from morphine


her·o·in | \ˈher-ə-wən \

Kids Definition of heroin

: a very harmful illegal drug that is highly addictive and is made from morphine


her·o·in | \ˈher-ə-wən \

Medical Definition of heroin 

: 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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More from Merriam-Webster on heroin

Spanish Central: Translation of heroin

Nglish: Translation of heroin for Spanish Speakers

Britannica English: Translation of heroin for Arabic Speakers

Britannica.com: Encyclopedia article about heroin

Comments on heroin

What made you want to look up heroin? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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