psychedelic

American  

[sahy-ki-del-ik] / ˌsaɪ kɪˈdɛl ɪk /

Sometimes psychodelic

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.

   LSD users seek the psychedelic properties of the drug, including heightened sensory experiences.

2. of, relating to, or noting any of various drugs producing this state, such as LSD, mescaline, or psilocybin.

   Researchers have long been interested in the potential therapeutic effects of psychedelic drugs for humans.

3. characterized by images, sounds, or feelings resembling those experienced while in the altered state produced by psychedelic drugs: The psychedelic designs of music posters in the 60s were inspired by the Art Nouveau movement of the late 1800s.

   Their music had a dreamy psychedelic sound, with gentle guitars and hushed vocals.

   The psychedelic designs of music posters in the 60s were inspired by the Art Nouveau movement of the late 1800s.

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noun

1. a psychedelic drug.

   The clinic will start treating patients with ketamine, a psychedelic.

2. Rare. a person who uses such a substance.

psychedelic British  

/ ˌsaɪkɪˈdɛlɪk /

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

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psychedelic Cultural  

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

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Discover More

Psychedelic art, most popular during the late 1960s and early 1970s, combines patterns, objects, light, and sound to simulate hallucinatory experiences.

Other Word Forms

• prepsychedelic adjective
• psychedelically adverb

Etymology

Origin of psychedelic

First recorded in 1956; from psyche + Greek dêl(os) “visible, manifest, evident” + -ic

Example Sentences

The attempt went relatively smoothly, she explains, apart from a "nightmarish" section when cleaning a kid's playground at four in the morning where the game's bright primary colours affected her in "a very psychedelic way".

From BBC • Apr. 3, 2026

"Our findings are consistent with a growing scientific perspective suggesting that psychedelic effects and serotonergic activity may be dissociated," says Andrea Mattarei, a corresponding author of the study.

From Science Daily • Mar. 8, 2026

Hartman is a journalist living in Los Angeles and the publisher of DoubleBlind, a magazine and media company at the forefront of the psychedelic movement.

From Los Angeles Times • Feb. 24, 2026

Part of the beauty and profundity of people’s psychedelic experiences is the ineffable—but the systems that run on Western science are hungry for hard data, replicable and reliable outcomes, and, perhaps most importantly, profit.

From Slate • Jan. 30, 2026

The association with the method is unfortunate, because unlike the large psychedelic Deadhead patterns and colors, bandini tie-dyes are delicate and intricate.

From "Love, Hate & Other Filters" by Samira Ahmed

Related Words

• hallucinatory
• kaleidoscopic
• multicolored