A bitch to bring as back up to an event such as a concert, party, etc... basically any social event, as insurance for getting laid incase the social event isn't providing bitches that are bangable.
Awesome guy one: "dude! let's go see def leppard and hit on some milfs!"
Awesome guy two: "i'm down but we better bring some back up bitches incase they all turn out to be cracked out moms."
A sexual act in which a woman or a man goes down on an erect penis, jamming the penis down his/her throat until he/she chokes on the penis and purges all over the penis and balls; following the purging, he/she proceeds to finish the man off with his/her mouth or hand, using the throw-up as a lube.
Becky and Bob took turns giving Rick a purge job, each enjoying the taste of eachother's green lube.