When a song is so big it's not just a Phat tune it's a Morbidly Obese Tune..... Mostly used around the cinema/restaurant area at Bury St edmunds, Suffolk.

Also called MO Tune for short!!
Guy 1: Man This is a Phat Tune...
Guy 2: No mate this is a Morbidly Obese Tune...
Guy 1:True.....MO TUNE!!!!
Guy 2:..MO TUNE!!!
by Kitchen Gods J.V January 18, 2010
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