1. Of, characterized by, or generating hallucinations, distortions of perception, altered states of awareness, and occasionally states resembling psychosis.
2. Suggestive or evocative of an altered or hallucinatory state of perception: psychedelic patterns; psychedelic music.
A drug, such as LSD or mescaline, that produces psychedelic effects.
[PSYCHE1 + Greek dēloun, to make visible (from dēlos, clear, visible; see dyeu- in the Appendix of Indo-European roots) + -IC.]
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