The world of tattoo art and design has its own language and terminology as well as any company does. A more contemporary terms in business is the mark of a vagabond. "What are tramp stamps? Well, they have nothing to do with the U.S. mail or a picture on a postage stamp or even children of the classic Disney film Lady and the Tramp."
A tramp stamp is a term that was coined (Unknown Source) to describe a tattoo that is printed on the back of a woman or a girl. The lower back has become a popular place for women to get inked and combined with the tendency of low-rise jeans has led to an avalanche of tattoo studios. It has become fashionable for girls to show their bellies with belly rings and body piercings and tattoos lower back with body art.
The term tramp stamp is a derogatory tone, and should not be considered as relevant when deciding to get body art. Getting a tattoo is a personal decision that has nothing to do, as a note. Another popular trend is for women to get sexy foot and ankle tattoos. There is negative marking, or a reaction to these places, or even more sexually explicit Areas of the breasts and genitalia, although these are less places for tattoos - they are doing, however, have more sexual nature - and even lower back has gotten more attention.