A word commonly used to describe a person, mostly women, who have a big butt. This butt has a very big "span" and is usually found on people who are overweight.
LaShonday: "DAAAAMN BONIFA! DID YOU SEE THAT SPANTAAANEOUS BOOTAY?"

Bonifa: "OH MA GAAD! THE GIRL FROM PRECIOUS!!!" *runs up to Spantaneous Bootay*

Bonifa:"OH SHIIIT! DATS A DUUDE!"
by Tsavorio April 13, 2010
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