Rav Waxman said: (in reference to a thread on beards) "2) In terms of hair covering, lehalacha, there are two different levels, as the gemara in Ketubot 72 makes clear. There is the Biblical level and the level of Dat Yehudit. The Mishna is not talking about the hair entirely uncovered, but rather with a basket-hat, a kalta. This is not "erva" in the Biblical sense, but if a woman violates Dat Ye…