Acronym for "Can't Have A Larger Upper Pussy Area." It is obviously the most extreme of the "upper pussy area" terms. It rhymes with FUPA (Fat Upper Pussy Area), producing the ultra-effective and scintillating term "FUPA CHALUPA."
The irony of a chalupa being similar to a taco and a taco possessing likeness to a vagina add to the word's efficacy.
Did you see that obese girl's CHALUPA?! It was hanging lower than Helga's fupa!