One penetrates the anal or vaginal crevice of one's partner from behind, while repeatedly fist-pumping said partner's ass cheek to the point of bruising.
Hellen got jersey punched last night while eating a burrito, leaving a nasty birthday tattoo.
Unidentified bruise resulting from a blackout on your birthday.
Nancy received a nasty birthday tattoo last night and doesn't remember a thing. We think she may have been jersey punched.