Source : WordNet®

psychedelic
     adj 1: producing distorted sensory perceptions and feelings or
            altered states of awareness or sometimes states
            resembling psychosis; "psychedelic drugs like
            psilocybin and mescaline"
     2: having the vivid colors and bizarre patterns associated with
        psychedelic states; "a psychedelic painting"
     3: of a mental state characterized by intense and distorted
        perceptions and hallucinations and feelings of euphoria or
        sometimes despair; "a psychedelic experience"