Skin Yamaka (Yarmulke)
When a middle aged man is balding only in the spot where a Jewish Yamaka (Yarmulke) would be worn.
Student 1: Dude, our teacher is getting old. I think he's balding!
Student 2: Yeah! I think he has a Skin Yamaka (Yarmulke)!
Student 2: Yeah! I think he has a Skin Yamaka (Yarmulke)!