Shipoopy is a street name for an unobtainable girl. The word became more widely known when used as the subject matter for a song by Peter Griffin in 'Family Guy'. Peter Griffin is the second coming of Our Lord, and his power is over 9000.
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The song 'Shipoopi' was not made for use on Family Guy. Everyone thinks that, but each one of them is a Baka. The song 'Shipoopi' was written by Meredith Wilson for the musical The Music Man. If anything, Family Guy took the song from The Music Man, not the other way around.