[sil-uh-sahy-bin, sahy-luh-]

noun Pharmacology.

a hallucinogenic crystalline solid, C12H17N2O4P, obtained from the mushroom Psilocybe mexicana.

Origin of psilocybin

1955–60; < New Latin Psilocyb(e) genus of mushrooms (< Greek psīló(s) bare + kýbē head) + -in2 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for psilocybin

Contemporary Examples of psilocybin

  • It lasts several hours longer than either MDMA or psilocybin, and it has the greatest risk profile of any psychedelic.

    The Daily Beast logo
    Is LSD Good for You?

    Paul Schrodt

    August 19, 2009

Historical Examples of psilocybin

British Dictionary definitions for psilocybin



a crystalline phosphate ester that is the active principle of the hallucinogenic fungus Psilocybe mexicana. Formula: C 12 H 17 N 2 O 4 P

Word Origin for psilocybin

C20: from New Latin Psilocybe (from Greek psilos bare + kubē head) + -in
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for psilocybin

1958, from Modern Latin psilocybe, name of a Central American species of mushroom, from Greek psilos "bare" (see psilo-) + kybe "head."

Online Etymology Dictionary, © 2010 Douglas Harper

psilocybin in Medicine


[sĭl′ə-sībĭn, sī′lə-]


A hallucinogenic compound obtained from the mushroom Psilocybe mexicana.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

psilocybin in Science


[sĭl′ə-sībĭn, sī′lə-]

A hallucinogenic compound obtained from certain mushrooms, especially of the genus Psilocybe. Chemical formula: C12H17N2O4P.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.