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definitions

psychedelic

[sahy-ki-del-ik]
See more synonyms for psychedelic on Thesaurus.com
adjective
  1. of or noting a mental state characterized by a profound sense of intensified sensory perception, sometimes accompanied by severe perceptual distortion and hallucinations and by extreme feelings of either euphoria or despair.
  2. of, relating to, or noting any of various drugs producing this state, as LSD, mescaline, or psilocybin.
  3. resembling, characteristic of, or reproducing images, sounds, or the like, experienced while in such a state: psychedelic painting.
noun
  1. a psychedelic drug.
  2. a person who uses such a substance.
Also psychodelic.

Origin of psychedelic

1956; psyche + Greek dêl(os) visible, manifest, evident + -ic
Related formspsy·che·del·i·cal·ly, adverbpre·psych·e·del·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for psychedelic

hallucinatory, kaleidoscopic, multicolored, crazy, experimental, mind-blowing, trip, freaky, consciousness-expanding, hallucinogenic, mind-bending, mind-expanding, psychoactive, psychotomimetic, psychotropic

Examples from the Web for psychedelic

Contemporary Examples of psychedelic

British Dictionary definitions for psychedelic

psychedelic

psychodelic

adjective
  1. relating to or denoting new or altered perceptions or sensory experiences, as through the use of hallucinogenic drugs
  2. denoting any of the drugs, esp LSD, that produce these effects
  3. informal (of painting, fabric design, etc) having the vivid colours and complex patterns popularly associated with the visual effects of psychedelic states
Derived Formspsychedelically or psychodelically, adverb

Word Origin for psychedelic

C20: from psyche + Greek delos visible
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 psychedelic
adj.

occasionally psychodelic, 1956, of drugs, suggested by British-born Canadian psychiatrist Humphry Osmond (1917-2004) in a letter to Aldous Huxley and used by Osmond in a scientific paper published the next year; from Greek psykhe- "mind" (see psyche) + deloun "make visible, reveal," from delos "visible, clear," from PIE root *dyeu- "to shine" (see diurnal). In popular use from 1965 with reference to anything producing effects similar to that of a psychedelic drug or enhancing the effects of such a drug. As a noun from 1956.

Online Etymology Dictionary, © 2010 Douglas Harper
psychedelic in Medicine

psychedelic

[sī′kĭ-dĕl′ĭk]
adj.
  1. Of, characterized by, or generating hallucinations, distortions of perception, altered states of awareness, and occasionally states resembling psychosis.
n.
  1. A drug, such as LSD or mescaline, that produces such effects.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
psychedelic in Culture

psychedelic

[(seye-kuh-del-ik)]

A descriptive term for things that produce or are related to hallucinations, especially drugs such as LSD.

Note

Psychedelic art, most popular during the late 1960s and early 1970s, combines patterns, objects, light, and sound to simulate hallucinatory experiences.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.