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

Even with those limitations, the researchers concluded, "Vitamin D deficiency is associated with a higher occurrence of moderate to severe postoperative pain and increased opioid consumption in patients undergoing unilateral modified radical mastectomy."

From Science Daily • May 20, 2026

In addition, Molo’s firm represented the Cherokee Nation against opioid manufacturers.

From The Wall Street Journal • May 10, 2026

Administration fees in similar opioid victim funds, also run by Gentle, range from about 15% to more than one-quarter of the victims’awards, according to documents from those trusts.

From Salon • Apr. 24, 2026

The Pitt covers everything from a measles outbreak, a shooting at a festival, the opioid crisis, medical abortion, black maternal care, homelessness and more besides.

From BBC • Mar. 27, 2026

Kaufmann stepped down after steering the company through an onslaught of litigation related to the opioid crisis.

From Barron's • Feb. 5, 2026