Standard Lemma guide

naloxone

noun · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • Received-Pronunciation: /nəˈlɒk.səʊn/
  • General-American: /nəˈlɑkˌsoʊn/

1

noun

Meaning 1

An opioid inverse agonist used to counter the effects of an overdose on opioids (such as heroin or morphine).

Definition source: English Wiktionary via Wiktextract

Usage: uncountable

Topics: medicine, pharmacology, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

a potent narcotic antagonist (trade name Narcan) especially effective with morphine

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: Narcan

Antonyms: none provided

Broader terms: narcotic antagonist

History

Etymology

Etymology tree English nal- Proto-Indo-European *wed- Proto-Indo-European *-r̥ Proto-Indo-European *wódr̥ Proto-Hellenic *údōr Ancient Greek ῡ̆̔́δωρ (hū̆́dōr) Ancient Greek ῠ̔δρο- (hŭdro-)der. English hydro- English oxy English (hydr)ox(y) German Ketonbor. English ketone English -one English naloxone From nal- (“opioid receptor antagonist/agonist”) + (hydr)ox(y) + -one.

Across languages

Translations

4 source translations are retained for this English entry.

  • Chinese Mandarin: 納洛酮 /纳洛酮 (nàluòtóng) — opioid drug
  • Kazakh: налоксон (nalokson) — opioid drug
  • Russian: налоксон (nalokson) — opioid drug
  • Spanish: naloxona — opioid drug