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

At that point, Colorado and Oregon had yet to legalize psilocybin use, but interest in the drugs as mental health aids was growing. —Meg Wingerter, The Denver Post, 28 Jan. 2025

In states like Oregon, psilocybin therapy is now available, and in Canada, the regulatory environment is moving toward the legalization of psychedelics for therapeutic use. —Matt Rozo, The Mercury News, 7 Jan. 2025

Two of the closest behind Lykos are in the midst of trials looking at psilocybin to treat depression — Compass Pathways and the Usona Institute. —Dylan Matthews, Vox, 2 Jan. 2025

The big picture: Psychedelics are emerging as a promising tool for treating mental health disorders, with over 200 clinical trials on psilocybin underway worldwide. —Christine Clarridge, Axios, 5 Dec. 2024

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)