unclipped

A penis that for whatever reason isn't circumcised

Peter: Did you see Jon in the locker room?
Mike: No, why?
Peter: He's unclipped!
Mike: Eww, I thought everyone was circumcised these days?
Peter: Apparently not Jon

unclipped horn

an uncircumcised penis

If you have an unclipped horn, be sure to clean the lint out of your penis hood.