psi·​lo·​cy·​bin | \ ˌsī-lə-ˈsī-bən How to pronounce psilocybin (audio) \

Definition of psilocybin

: 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 Hodges is accused of bringing psilocybin mushrooms, a hallucinogenic commonly known as magic mushrooms, to a friend, who is a resident of the Briar Place Nursing and Rehabilitation center, at 6800 Joliet Road. Kimberly Fornek,, "Western Springs police blotter: Man charged with delivering drugs to friend at Briar Nursing Place," 16 Apr. 2021 Particularly of note is the fact that the study assessed the effects of psilocybin against an antidepressant rather than a placebo, as previous studies have done. Ej Dickson, Rolling Stone, "Could Psilocybin Be as Effective as Antidepressants?," 15 Apr. 2021 House Bill 1802 would direct the Health and Human Services Commission to conduct the clinical study of psilocybin in partnership with a health sciences university and a Veterans Affairs hospital. Patrick Svitek, Dallas News, "Rick Perry returns to Texas Capitol to back study of psychedelic drugs for PTSD in veterans," 14 Apr. 2021 Thirty participants received two 25 mg doses of psilocybin three weeks apart, as well as six weeks of a daily placebo pill. Kaitlin Sullivan, NBC News, "Psychedelic drug worked for depression as well as common antidepressant, small trial finds," 14 Apr. 2021 Oregon’s first-in-the-nation program to allow regulated, therapeutic use of psilocybin got underway Tuesday when Gov. Kate Brown announced the members of the Oregon Psilocybin Advisory Board. oregonlive, "Governor appoints board to oversee Oregon’s new psychedelic mushroom program," 16 Mar. 2021 Our lead engineer studied the effects of psilocybin on the brain in the late Seventies and spent the last 25 years trying to recreate that positive neurological activation through sensory inputs. Paul Jebara, Forbes, "The Art Of Reaching Flow State, According To IRIS Founder Jacobi Anstruther-Gough-Calthorpe," 9 Mar. 2021 Just one dose of psilocybin, the active ingredient in magic mushrooms, was recently shown to ease depression and anxiety in cancer patients—an outcome that lasted for years after their trip. Mandy Oaklander, Time, "Inside Ibogaine, One of the Most Promising and Perilous Psychedelics for Addiction," 5 Apr. 2021 In the last decade, researchers in the U.S. have performed dozens of studies of psychedelics—among them MDMA; psilocybin, the active ingredient in magic mushrooms; and LSD—to treat individuals with anxiety, depression, PTSD and addiction. Laura Cooper, WSJ, "Could Group Therapy Get a Boost From Psychedelics?," 10 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'psilocybin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of psilocybin

1958, in the meaning defined above

History and Etymology for psilocybin

New Latin Psilocybe, fungus genus + -in entry 1

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Time Traveler for psilocybin

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The first known use of psilocybin was in 1958

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Last Updated

29 Apr 2021

Cite this Entry

“Psilocybin.” Dictionary, Merriam-Webster, Accessed 10 May. 2021.

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More Definitions for psilocybin


psi·​lo·​cy·​bin | \ ˌsī-lə-ˈsī-bən How to pronounce psilocybin (audio) \

Medical Definition of psilocybin

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

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