PSYCHEDELIC
psychedelic
(adjective) (of a mental state) characterized by intense and distorted perceptions and hallucinations and feelings of euphoria or sometimes despair; “a psychedelic experience”
psychedelic
(adjective) having the vivid colors and bizarre patterns associated with psychedelic states; “a psychedelic painting”
psychedelic
(adjective) producing distorted sensory perceptions and feelings or altered states of awareness or sometimes states resembling psychosis; “psychedelic drugs like psilocybin and mescaline”
Source: WordNet® 3.1
Etymology
Adjective
psychedelic (comparative more psychedelic, superlative most psychedelic)
Of, containing, generating, or reminiscent of drug-induced hallucinations, distortions of perception, altered awareness etc.
(of graphics, etc.) Having bright colours, abstract shapes, etc. reminiscent of drug-induced hallucinations or distortions of perception.
Synonyms
• (of hallucinations): lysergic, trippy
• (having bright colours): multi-coloured
Noun
psychedelic (plural psychedelics)
Any psychoactive substance (such as LSD or psilocybin) which, when consumed, causes perceptual changes (sometimes erratic and uncontrollable), visual hallucination, and altered awareness of the body and mind.
Interjection
psychedelic
(hippie slang) awesome, cool, groovy
Source: Wiktionary