Coined by the psychiatrist Humphrey Osmond while corresponding with author Aldous Huxley, the word psychedelic was introduced to the public in 1957. It is composed of two Greek roots: the noun psychē (ψυχή), meaning "soul, mind," and the verb dēlóō (δηλόω), meaning "to manifest." The idea was that certain hallucinogenic drugs that triggered non-ordinary states of consciousness were "mind manifesting" or even "soul manifesting" medicines that could expand the unused potential of the human mind, hence the term psychedelic.