1

opioid

adjective opi·oid \ ˈō-pē-ˌȯid \
|Updated on: 14 Jun 2018

Definition of opioid

1 : possessing some properties characteristic of opiate narcotics but not derived from opium
2 : of, involving, or induced by an opioid

Recent Examples of opioid from the Web

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

1967

in the meaning defined at sense 1

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2

opioid

noun

Definition of opioid

1 : any of a group of endogenous neural polypeptides (such as an endorphin or enkephalin) that bind especially to opiate receptors and mimic some of the pharmacological properties of opiates called also opioid peptide
2 : a synthetic drug possessing narcotic properties similar to opiates but not derived from opium; broadly : opiate 1a

Recent Examples of opioid from the Web

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

1957

in the meaning defined at sense 2

See Words from the same year
NEW! Time Traveler

Medical Dictionary

1

opioid

adjective opi·oid \ ˈō-pē-ˌȯid \

medical Definition of opioid

1 : possessing some properties characteristic of opiate narcotics but not derived from opium
2 : of, involving, or induced by an opioid

2

opioid

noun

medical Definition of opioid

1 : any of a group of endogenous neural polypeptides (as an endorphin or enkephalin) that bind especially to opiate receptors and mimic some of the pharmacological properties of opiates called also opioid peptide
2 a : a synthetic drug (as methadone) possessing narcotic properties similar to opiates but not derived from opium
b : opiate 1 not used technically

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