The mark that a woman has on her lower back usually in tattoo format. This originates from the porn industry where ladies being abused from behind were keen to have some kind of brand awareness in their movies. This was an easy way for the girls to be identified whilst their faces were out of shot.
That chick is bending over in those low cut jeans you can see her whoremark.

That porn star has a tribal whoremark on her lower back
by studlywonder November 13, 2007
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