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.

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adjective

1. pertaining to such a substance.

   opioid drugs such as heroin and oxycodone;

   opioid neuropeptides.

opioid British  

/ ˈəʊpɪˌɔɪd /

noun

1. 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

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Other Word Forms

Noun Inflected Forms

• opioids
  plural

Etymology

Origin of opioid

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

Example Sentences

See Examples For:

opioid opioids

In the past, courts have supplied this important backstop in other widespread policy challenges, such as the public health threats of tobacco use and the opioid epidemic, that lacked adequate legislative or regulatory responses.

From Slate ● Sep. 29, 2026

The department announced the settlement last week without initially providing specifics about the opioid deal.

From The Wall Street Journal ● Sep. 1, 2026

The findings suggest that chronic pain may interfere with the ability of mu opioid receptors to restrain activity in locus coeruleus brain cells.

From Science Daily ● Aug. 27, 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 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

Beginning with tobacco, they refitted the dusty doctrine as a battering ram and swung it at guns, lead paint, opioids and oil companies.

From The Wall Street Journal ● Jul. 19, 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

It includes 16 qualifying prescriptions for Purdue opioids listed on the trust’s website.

From Salon ● Apr. 24, 2026