psychedelic (adj.)

occasionally psychodelic, "producing expanded consciousness through heightened awareness and feeling," 1956, of drugs, suggested by British-born Canadian psychiatrist Humphry Osmond in a letter to Aldous Huxley and used by Osmond in a scientific paper published the next year; from Greek psykhē "mind" (see psyche) + dēloun "make visible, reveal" (from dēlos "visible, clear," from PIE root *dyeu- "to shine").

In popular use from 1965 with reference to anything producing effects or sensations similar to the common perception of the effects of a psychedelic drug. As a noun, "a psychedelic drug," from 1956.