pronounced "Mare-in-eight": To make someone you've made eye contact with several times with in one night, make the first move. A practice commonly used by shyer members of either sex.
Guy A: "You've been checkin' out those girls all night, go talk to one of them."
Guy B: "Nah, I'mma let them bitches marinate." (to general direction of girls) "Marinate bitches!"