Windex Booty
When a girl wears spandex or yoga pants so tight that you can clearly see through the pants, in turn reveling their thong, panties, and boy shorts etc. Thus, giving the same appearance of a clean window in which it is easy to view through.
Roger: Damn! did you see the chick in the spandex?
Joe: yeahh dude she had windex booty!
Joe: yeahh dude she had windex booty!