The word psychedelic is a neologism coined from the Greek words for "mind," ψυχή (psyche), and "manifest," δήλος (delos).
A psychedelic experience is characterized by the perception of aspects of one's mind previously unknown, or by the creative exuberance of the mind liberated from its ostensibly ordinary fetters. Psychedelic states are an array of experiences elicited by sensory deprivation as well as by psychedelic substances. Such experiences include hallucinations, changes of perception, synesthesia, altered states of awareness, mystical states, and occasionally states resembling psychosis.