a mushroom, Psilocybe mexicana, of Mexico and the southwestern U.S., containing the hallucinogen psilocybin.
Origin of magic mushroom
First recorded in 1965–70
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British Dictionary definitions for magic mushrooms
informal any of various types of fungi that contain a hallucinogenic substance, esp Psilocybe mexicana, which contains psilocybin
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