Boob to Belly Ratio
A comparison size between a woman's breasts and their belly/gut/etc. Ideally, men look for women who's breast ratio are larger than the belly. Likewise, women who have a bigger belly than they have breasts are said to violate the boob to belly ratio.
"dude, that girl over at the bar is hot!"
"You're kidding, right? She totally violates the boob to belly ratio!..."
"You're kidding, right? She totally violates the boob to belly ratio!..."