opioid

noun
opi·​oid | \ ˈō-pē-ˌȯid How to pronounce opioid (audio) \
plural opioids

Definition of opioid

 (Entry 1 of 2)

: a natural, semisynthetic, or synthetic substance that typically binds to the same cell receptors as opium and produces similar narcotic effects (such as sedation, pain relief, slowed breathing, and euphoria):
a or less commonly opioid peptide : any of various of endogenous polypeptides (such as an endorphin or enkephalin) produced by neurons of the peripheral and central nervous system The people who rated pain the lowest were those whose brains began producing natural painkillers called opioids the fastest …— John O'Neil
b : any of various opiates (such as morphine), semisynthetic opiate derivatives (such as heroin, hydrocodone, or oxycodone), or synthetic preparations (such as fentanyl or methadone) that may be used illicitly for their narcotic properties and are associated with physiological tolerance (see tolerance sense 4a(1)), physical and psychological dependence, or addiction upon repeated or prolonged use … fentanyl, a synthetic opioid at least 75 times more potent than morphine.— Ryan Trimble and Eric S. Peterson Naltrexone is an opioid antagonist used for the treatment of heroin addiction.Scientific American The prototypical opioids are morphine and codeine (which is milder than morphine).Harvard Health Letter When Walker County was identified as the epicenter of Alabama's opioid crisis, it was no surprise to residents who watched as drugs brought death and devastation down upon their families, neighbors and communities.— Ashley Remkus

Note: The word opioid was originally used only for morphine-like substances not derived from opium, but it has now become widely accepted as a broader term encompassing any substance—natural or synthetic, opium-derived or not—that binds to opiate cell receptors and induces sedation, analgesia, and euphoria.

opioid

adjective
\ ˈō-pē-ˌȯid How to pronounce opioid (audio) \

Definition of opioid (Entry 2 of 2)

: possessing narcotic properties characteristic of opiates : of, relating to, involving, or being an opioid opioid drugs opioid addiction endogenous opioid endorphins opioid cell receptors

Examples of opioid in a Sentence

Recent Examples on the Web: Noun The language called for legalizing the use of strips that test drugs for fentanyl, a potent synthetic opioid fueling a wave of fatal overdoses across Georgia and the U.S. Andy Miller, ajc, 6 May 2022 State health officials issued an alert this week to families and parents in schools around Alaska warning them of the dangers of fentanyl, the highly potent synthetic opioid that is killing Alaskans at a startling rate. Annie Berman, Anchorage Daily News, 4 May 2022 The language called for legalizing the use of strips that test drugs for fentanyl, a potent synthetic opioid fueling a wave of fatal overdoses across Georgia and the U.S. Andy Miller, CNN, 4 May 2022 Fentanyl, a synthetic opioid, is 80 to 100 times stronger than morphine and 50 times more potent than heroin, according to the Drug Enforcement Administration. NBC News, 21 Apr. 2022 One specific driver of these deaths was fentanyl, a synthetic opioid that the Drug Enforcement Administration says is 80 to 100 times stronger than morphine. Byeli Cahan, ABC News, 12 Apr. 2022 Health officials are still investigating what substance was cut into the cocaine, but said that early indications point to fentanyl, the potent and highly dangerous opioid that has caused a surge of drug overdose deaths in the U.S. Ryan Dube, WSJ, 3 Feb. 2022 But what was in her bloodstream was fentanyl, a synthetic opioid 100 times more potent than morphine. John Keilman, chicagotribune.com, 9 Nov. 2021 The sheriff’s office described fentanyl as a synthetic opioid that is as many as 100 times stronger than morphine. Brianna Kwasnik, Arkansas Online, 26 Apr. 2022 Recent Examples on the Web: Adjective The state House of Representatives and Senate were debating simultaneously in an all-day marathon to approve bills combatting opioid abuse, promoting economic development, and reducing juvenile crime. Christopher Keating, Hartford Courant, 5 May 2022 As an adult, Valentin Broeksmit had a history of opioid abuse. Nathan Solis, Los Angeles Times, 29 Apr. 2022 Maryland began requiring public schools to carry naloxone and to educate students about the risk of opioid abuse in 2018. Daniela Altimari, courant.com, 17 Jan. 2022 Buprenorphine to help people medically transition away from opioid abuse. IndyStar, 16 Dec. 2021 Seeking capital punishment in drug cases is part of the Trump administration’s efforts to combat opioid abuse. CNN, 12 Dec. 2021 The federal government says nearly a half-million Americans have died from opioid abuse since 2001. Fox News, 15 Nov. 2021 Guidelines meant to prevent opioid abuse have blocked their access to legitimate treatment. Tess Vrbin, Arkansas Online, 27 Oct. 2021 Galluci said that even though the trial focuses on what transpired between 2006 to 2014, the wave of opioid abuse still afflicts both counties. Washington Post, 3 Oct. 2021 See More

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

First Known Use of opioid

Noun

1957, in the meaning defined above

Adjective

1967, in the meaning defined above

History and Etymology for opioid

Noun

opium + -oid entry 1

Adjective

opium + -oid entry 2

Learn More About opioid

Dictionary Entries Near opioid

opio-

opioid

opiophile

See More Nearby Entries 

Statistics for opioid

Last Updated

15 May 2022

Cite this Entry

“Opioid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/opioid. Accessed 21 May. 2022.

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More Definitions for opioid

opioid

adjective
opi·​oid | \ ˈō-pē-ˌȯid \

Medical Definition of opioid

 (Entry 1 of 2)

: possessing narcotic properties characteristic of opiates : of, relating to, involving, or being an opioid opioid drugs opioid addiction endogenous opioid endorphins opioid cell receptors

opioid

noun

Medical Definition of opioid (Entry 2 of 2)

: a natural, semisynthetic, or synthetic substance that typically binds to the same cell receptors as opium and produces similar narcotic effects (as sedation, pain relief, slowed breathing, and euphoria):
a or less commonly opioid peptide : any of various of endogenous polypeptides (as an endorphin or enkephalin) produced by neurons of the peripheral and central nervous system
b : any of various opiates (as morphine), semisynthetic opiate derivatives (as heroin, hydrocodone, or oxycodone), or synthetic preparations (as fentanyl or methadone) that may be used illicitly for their narcotic properties and are associated with physiological tolerance (see tolerance sense 1), physical and psychological dependence, or addiction upon repeated or prolonged use … fentanyl, a synthetic opioid at least 75 times more potent than morphine.— Ryan Trimble and Eric S. Peterson The prototypical opioids are morphine and codeine (which is milder than morphine).Harvard Health Letter

Note: The word opioid was originally used only for morphine-like substances not derived from opium, but it has now become widely accepted as a broader term encompassing any substance—natural or synthetic, opium-derived or not—that binds to opiate cell receptors and induces sedation, analgesia, and euphoria.

More from Merriam-Webster on opioid

Britannica.com: Encyclopedia article about opioid

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