heroin

noun

her·​o·​in ˈher-ə-wən 

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 

ˈhe-rə-

noun

Examples of heroin in a Sentence

Recent Examples on the Web

But everybody is against fentanyl, heroin and cocaine. —Stephanie Nolasco, FOXNews.com, 8 Nov. 2025

An investigation into a man suspected of selling drugs out of his car in East Oakland culminated in his arrest Thursday, as well as the seizure of nearly $475,000, more than 25 pounds of heroin and a half-dozen handguns, authorities said. —Jason Green, Mercury News, 7 Nov. 2025

This includes heroin, cocaine, opioids like fentanyl and oxycodone, methamphetamine, suboxone and synthetic marijuana. —Miami Herald, 7 Nov. 2025

Joslin was fighting a heroin addiction, according to the memo. —Chris Spargo, PEOPLE, 31 Oct. 2025

Word History

Etymology

from Heroin, a trademark

First Known Use

1898, in the meaning defined above

Rhymes for heroin

• heroine

Kids Definition

heroin

noun

her·​o·​in ˈher-ə-wən 

: a strongly addictive drug made from the opium poppy and stronger than morphine

Medical Definition

heroin

noun

her·​o·​in ˈher-ə-wən 

: 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