The term psychedelic developed out of correspondence between Aldous Huxley and Humphry Osmond, both of whom were pursuing the subject. Both wanted a term that described the visionary, argualby mystical, and possibly healing nature of hallucinogens, but that did not have a pathological inference. In 1956, Osmond proposed psychedelic, deriving from Greek psyche, soul, and delos, visible or manifest, hence meaning soul- or mind-manifesting. Huxley proposed phanerothyme, and the men exchanged ditties. Huxley wrote:
To make this trivial world sublime,
Take half a gram of phanerothyme.
But Osmond won out with:
To fathom hell or soar angelic,
Just take a pinch of psychedelic.
The term came into common usage in the 1960s, and was applied not only to the psychoactive substances themselves, but to everything that seemed to either inspire or be inspired by their use in music, art, or fashion. Because of this generalized usage, and because of its inadequacy as a precise descriptor of the otherworldly effects associated with psychoactive substances, some people dislike the term. Some researchers have proposed that psychedelic should be replaced by entheogenic, which has Greek origins meaning realizing the divine within. They would also replace hallucinogens with entheogens. As laudalbe as this attempt may be, it is unlikely that the unwieldly entheogenic will ever replace psychedelic in common parlance.
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GREAT PSYCHEDELIC MUSIC:

J.D. Blackfoot - The Ultimate Prophecy
Steaming hot psychedelic rock classic with great guitars and mad lyrics! The concept is the life cycle explained by psych guru J.D. Blackfoot.

El Alamo - Malos Pensamientos
Peruvian psychedelia! One of the best bands from Latin America. They sing in English and play acid guitars!

Traffic Sound - Virgin (Tomorrow)
The kings of Incarock! Backward vocals, mescalin drenched guitar solos and Aztec precussion makes this one a winner!

Gerardo Manuel & El Humo: Apocallupsis
The first album by Gerardo Manuel, the undisputed shaman of Latin spacerock! Tripped out arrangements and monster guitar riffing!