hallucinogen

noun

hal·​lu·​ci·​no·​gen hə-ˈlü-sə-nə-jən How to pronounce hallucinogen (audio)
: a substance that induces hallucinations
hallucinogenic
hə-ˌlü-sə-nə-ˈje-nik How to pronounce hallucinogen (audio)
adjective or noun

Examples of hallucinogen in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The hallucinogen is known to raise the risk of abnormal heart rhythms and rates and could cause vomiting. — Jacqueline Howard, CNN Money, 22 Apr. 2026 Use of naturally occurring and synthetic hallucinogens traces back to the Neanderthals. — Jerel Ezell, STAT, 1 May 2026 Previous national surveys have grouped psilocybin with other hallucinogens and focused on lifetime use rather than during the previous 12 months. — Ashley MacKin Solomon, San Diego Union-Tribune, 28 Apr. 2026 As part of the case, the court will consider narrowing a landmark 1990 decision over the spiritual use of peyote, a cactus that contains a hallucinogen called mescaline. — ABC News, 20 Apr. 2026 See All Example Sentences for hallucinogen

Word History

Etymology

hallucination + -o- + -gen

First Known Use

1954, in the meaning defined above

Time Traveler
The first known use of hallucinogen was in 1954

Browse Nearby Words

hallucinatory
hallucinogen
hallucinosis
See all Nearby Words

Cite this Entry

“Hallucinogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hallucinogen. Accessed 7 Jul. 2026.

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Kids Definition

hallucinogen

noun
hal·​lu·​ci·​no·​gen hə-ˈlü-sə-nə-jən How to pronounce hallucinogen (audio)
: a drug that causes hallucinations
hallucinogenic
-ˌlü-sə-nə-ˈjen-ik How to pronounce hallucinogen (audio)
adjective

Medical Definition

hallucinogen

noun
hal·​lu·​ci·​no·​gen hə-ˈlüs-ᵊn-ə-jən How to pronounce hallucinogen (audio)
: a substance and especially a drug that induces hallucinations

More from Merriam-Webster on hallucinogen

Nglish: Translation of hallucinogen for Spanish Speakers

Britannica.com: Encyclopedia article about hallucinogen

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