psilocybin

noun

psi·​lo·​cy·​bin ˌsī-lə-ˈsī-bən How to pronounce psilocybin (audio)
: 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
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.
In 2023, the Legislature passed a bill to decriminalize the personal use of psilocybin mushrooms and other psychedelics. — Grant Stringer, The Mercury News, 25 Mar. 2025 Adverse effects of psilocybin, including headache and nausea, typically resolve within one to two days. — Kate Ruder | Kff Health News, ABC News, 24 Mar. 2025 Randal Vance bragged about giving children microdoses of psilocybin and encouraged other people to do the same, prosecutors said. — Julia Marnin, Sacramento Bee, 21 Mar. 2025 Three North County residents are accused of utilizing children to help grow and distribute psilocybin mushrooms, according to a San Diego federal grand jury indictment. — City News Service, San Diego Union-Tribune, 21 Mar. 2025 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

Browse Nearby Words

psilate
psilocybin
psilomelane
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Cite this Entry

“Psilocybin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psilocybin. Accessed 1 Apr. 2025.

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Kids Definition

psilocybin

noun
psi·​lo·​cy·​bin ˌsī-lə-ˈsī-bən How to pronounce psilocybin (audio)
: a chemical that is obtained from a fungus and causes hallucinations

Medical Definition

psilocybin

noun
psi·​lo·​cy·​bin ˌsī-lə-ˈsī-bən How to pronounce psilocybin (audio)
: a hallucinogenic indole C12H17N2O4P obtained from a basidiomycetous fungus (as Psilocybe mexicana or P. cubensis synonym Stropharia cubensis)

More from Merriam-Webster on psilocybin

Britannica.com: Encyclopedia article about psilocybin

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