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.
The order’s singling out of ibogaine, the only psychedelic mentioned by name, surprised analysts, given how much less research exists on it than on psilocybin or MDMA. — Michelle Lhooq, New Yorker, 7 Aug. 2026 Troopers also allegedly found several bags of psilocybin mushrooms, according to state police. — Justin Muszynski, Hartford Courant, 7 Aug. 2026 If confirmed in larger trials, these results suggest that psilocybin therapy could kick-start anorexia recovery and provide relief. — Alexandra Pattillo, Scientific American, 5 Aug. 2026 When psilocybin enters the body, it gets broken down into a chemical called psilocin. — Helen Carefoot, Flow Space, 5 Aug. 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

Browse Nearby Words

psilate
psilocybin
psilomelane
See all Nearby Words

Cite this Entry

“Psilocybin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psilocybin. Accessed 14 Aug. 2026.

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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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