A sorority girl who's main goal in life is to have sex with as many fraternity guys as possible, and who's ultimate goal is to bang the starting quarterback. Once they have accomplished that, they focus on banging pretty much every other athlete on campus. It is possible to identify a Sorostitute if they are driving down the road blasting any 50 Cent song.
along with the other fine definitions already posted, i would like to add 'A chick that goes to college on some easy, useless (social services or anything that applies to child rearing) curricullum; with the sole intent of finding a man who will eventually graduate and support her in the style to which she'd like to become accustomed'
stay away from that sorostitute, she thinks going down is something you don't do after college