adjective

1. of or causing extreme changes in the conscious mind, as hallucinations, delusions, intensification of awareness and sensory perception, etc.
2. of or associated with psychedelic drugs; specif., simulating the auditory or visual effects of the psychedelic state
3. designating any of various fluorescent colors popularized during the 1960s

Etymology: < psyche + Gr dēloun, to make manifest

noun