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

The San Joaquin County District Attorney's Office said evidence presented during the trial showed Sherman was drunk and had taken psilocybin, also known as magic mushrooms, in his Lodi apartment prior to meeting Makinano outside Garry's Lounge that night. —Richard Ramos, CBS News, 20 June 2026

With consent from her legal guardians, the woman was enrolled in a psilocybin trial in Brazil. —Vanessa Etienne, PEOPLE, 15 June 2026

The drug showed signs of being clinically effective too, though Yaden is not yet fully sold on the idea that shorter-acting psychedelics can have the same therapeutic pop as a daylong trip on psilocybin. —Ross Andersen, The Atlantic, 12 June 2026

As the patient may have experienced natural fluctuations in her medical condition, the study could not establish that psilocybin directly caused the woman’s improvements. —Melissa Rudy, FOXNews.com, 9 June 2026

Word History

Etymology

New Latin Psilocybe, fungus genus + -in entry 1

First Known Use

1958, in the meaning defined above

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)