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opioid

American  
[oh-pee-oid] / ˈoʊ piˌɔɪd /

noun

Biochemistry, Pharmacology.
  • opioids
    plural
  1. an opiate, or any similar synthetic compound: formerly referring only to the latter, but now the predominant term for both the opium-derived and synthetically produced substances.

    Illicit use of the synthetic opioid fentanyl is on the rise.

    The opium poppy is the source for all natural opioids.

  2. any opiumlike substance.

    Have any opioids been detected in poppies that do not contain opium?

  3. any of a group of natural substances, as the endorphins, produced by the body in increased amounts in response to stress and pain.


adjective

  1. pertaining to such a substance.

    opioid drugs such as heroin and oxycodone;

    opioid neuropeptides.

opioid British  
/ ˈəʊpɪˌɔɪd /

noun

    1. any of a group of substances that resemble morphine in their physiological or pharmacological effects, esp in their pain-relieving properties

    2. (modifier) of or relating to such substances

      opioid receptor

      opioid analgesic

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of opioid

First recorded in 1955–60; opi(um) + -oid

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The committee voted against one peptide called Emideltide, evaluated for opioid withdrawal, chronic insomnia, and narcolepsy.

From The Wall Street Journal Jul. 24, 2026

They narrowly voted to exclude emideltide, which has been considered for insomnia, narcolepsy and opioid withdrawal, with numerous other marketing claims including stress, pain and cancer.

From Barron's Jul. 24, 2026

Emideltide: The FDA committee largely voted “no” on this peptide, which has been promoted as a tool to address insomnia, narcolepsy and opioid withdrawal.

From MarketWatch Jul. 24, 2026

The announcement includes charges against 90 medical professionals and targets a range of alleged schemes, such as wound care and opioid distribution.

From The Wall Street Journal Jun. 23, 2026

Overall, the evidence does not support routine opioid use for acute pain.

From Science Daily Jun. 9, 2026

The increase in endogenous opioids is especially interesting for pain research.

From Science Daily Aug. 9, 2026

The White House said the global exemption was being used to "evade tariffs and funnel deadly synthetic opioids" to the US.

From BBC Jul. 27, 2026

About two decades ago, Turner said, the healthcare industry started acknowledging the limits and risks of prescribing opioids for chronic pain.

From Los Angeles Times Jun. 19, 2026

Some jurors accused colleagues of letting their sympathy for children harmed by opioids cloud their ability to make decisions based on the law.

From The Wall Street Journal May 20, 2026

Most significantly, the new plan removed a key provision that allowed victims to submit a sworn affidavit, in lieu of a prescription or other medical or legal records, to prove they purchased Purdue opioids.

From Salon Apr. 24, 2026

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