psilocybin

noun

psi·lo·cy·bin ˌsī-lə-ˈsī-bən

: a hallucinogenic indole C₁₂H₁₇N₂O₄P obtained from a fungus (such as Psilocybe mexicana or P. cubensis synonym Stropharia cubensis)

Examples of psilocybin in a Sentence

Recent Examples on the Web

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One with the world To find out which parts of the brain were doing the work, the team replaced one network’s psilocybin activity with its sober version and checked how badly the classifier degraded. — Jacek Krywko, ArsTechnica, 10 Oct. 2026 The lead author, Roland Griffiths, gave three dozen healthy adults with no history of drug use a large dose of psilocybin. — Claire Hoffman, Rolling Stone, 21 Sep. 2026 Days after the executive order, the FDA issued national priority vouchers to companies studying psilocybin for treatment-resistant depression and major depressive disorder and metylone for post-traumatic stress disorder. — Brenda Goodman, CNN Money, 21 Sep. 2026 This means that psilocybin use could benefit a wide range of patients at different stages of cancer. — Rachel Raposas, PEOPLE, 7 Sep. 2026 See All Example Sentences for psilocybin

Word History

Etymology

New Latin Psilocybe, fungus genus + -in entry 1

First Known Use

1958, in the meaning defined above

Time Traveler

The first known use of psilocybin was in 1958

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Browse Nearby Words

psilate

psilocybin

psilomelane

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Cite this Entry

Style

“Psilocybin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psilocybin. Accessed 20 Oct. 2026.

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Kids Definition

psilocybin

noun

psi·lo·cy·bin ˌsī-lə-ˈsī-bən

: a chemical that is obtained from a fungus and causes hallucinations

Medical Definition

psilocybin

noun

psi·lo·cy·bin ˌsī-lə-ˈsī-bən

: a hallucinogenic indole C₁₂H₁₇N₂O₄P obtained from a basidiomycetous fungus (as Psilocybe mexicana or P. cubensis synonym Stropharia cubensis)

psilocybin

noun

Examples of psilocybin in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Kids Definition

Medical Definition

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