It means nothing. Figurative speech for "similar." But literal meaning would make no sense because is an oxymoron. Like "Deafening silence," which refers to unbearable silence.

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To fall in hell or soar angellic,
you need a pinch... of "Psychedelic"

-Humphrey Fortescue Osmond, on how he coined the word.

Some beautiful sounds that can be downloaded for free:
http://www.generalfuzz.net/tunes.php