heroin

noun her·o·in \ ˈher-ə-wən , ˈhe-rə- \
Updated on: 15 Nov 2017

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

heroinism

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

Recent Examples of heroin from the Web

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.

Origin and Etymology of heroin

from Heroin, a trademark


HEROIN Defined for English Language Learners

heroin

noun

Definition of heroin for English Language Learners

  • : a powerful illegal drug that is made from morphine


HEROIN Defined for Kids

heroin

noun her·o·in \ ˈher-ə-wən \

Definition of heroin for Students

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

Medical Dictionary

heroin

noun 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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