An expression used to point out a female dressing provocatively in a public place, assumedly in hopes of attracting male affection or attention. Can be used as a compliment or as a negative remark, depending on the user’s tone or intent. Origin of the phrase refers to prostitutes working a corner, dressing to attract johns - however the phrase used this way is strictly for pointing out or identifying females dressed provocatively.
John: "Dude, check out the girl in the green tank top.
Dave: "Wow... like it's on sale."