Psilocybin mushrooms, or psilocybin-containing mushrooms, commonly known as magic mushrooms or as shrooms, are a type of hallucinogenic mushroom and a polyphyletic informal group of fungi that contain the prodrug psilocybin, which turns into the psychedelic psilocin upon ingestion. The most potent species are members of genus Psilocybe, such as P. azurescens, P. semilanceata, and P. cyanescens, but psilocybin has also been isolated from approximately a dozen other genera, including Panaeolus (including Copelandia), Inocybe, Pluteus, Gymnopilus, and Pholiotina.
Amongst other cultural applications, psilocybin mushrooms are used as recreational drugs. Psilocybin mushrooms were used ritualistically in pre-Columbian Mexico, but claims of their widespread ancient use are largely exaggerated and shaped by modern idealization and ideology.