The inner thigh rash that comes from walking continuously for extended periods of time. Onset of Kennywood Rash can come from hot temperatures, bad jeans, poor underwear choice, or a lack of protection, i.e. Gold Bond. Name comes from the thigh rash gotten from walking around Kennywood all damn day.
Guy 1: I need to get home and throw on some Gold Bond I have some fuckin serious Kennywood Rash.