1. adj. used to describe the shape and
texture of ones tits. Almost always used to describe any fat girls cleavage.
2. The extreme
sag of the
titty area, as if it were made of butter.
"I heard Tessa has
straight butter tits."
"Of course she does, she weighs about
403."
"Dammmmn"
"That hooker has the lumpiest
butter tits I've ever seen, I could barely get head from her."