psychedelic Definition

psychedelic
adj

1a. Said of a drug, especially LSD: inducing a state of altered consciousness characterized by an increase in perception, eg of colour, sound, etc, hallucinations, and an intensifying of emotions that will sometimes reveal significant underlying motivations;
1b. Said of an event or experience, etc: resembling such effects; bizarre;

Example: had a psychedelic vision
1c. Belonging or relating to this kind of drug, experience, etc

Example: the psychedelic 60s.
2. Said of perceived phenomena, eg colour, music, etc: startlingly clear and vivid, often with a complex dazzling pattern.

Derivative: psychedelically
adverb

Etymology: 1950s: from psyche + Greek delos clear.