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").
If you think this definition is OK (I believe it is not, and the source is simply bad: the sentences are not coherent), then how do you interpret
> 1956, of drugs
part?
Doesn't that mean basically that experience can't be "psychedelic", unless it is a consequence "of drugs" (by this definition)?
If you try to dig into the "letter", it also specifically names drug-induced experiences "psychedelic".
Wiktionary does not mention any kind of "expanded consciousness" except the "belief of ... power of weeds", which refers to "psychedelic" in the meaning of "induced by drugs".