What is your description of a ”hooker’s uniform”?

While passing a park that is known to be a hangout for less than reputable people (for lack of a better word), the friend I was with ask me of a young woman there was a prostitute. I asked him which woman he was speaking of, since there were a few, he said the gal with the ”Hooker’s uniform”. I have heard the term before, I ask you, if you had to describe it what would a ”hooker’s uniform” be? What articles of clothes comprise it or how certain clothes are worn to be a ”hooker’s uniform” in your mind?