köken: From a putative Middle Persian [Book Pahlavi needed] (*bwlyk' /bōrīg/) suffixed from [Book Pahlavi needed] (bwl /bōr/) becoming modern بور (bur, “red, bay; blond”) – compare Middle Persian [Book Pahlavi needed] (bwlk' /*bōrag/) reflected in modern بوره (bure, “borax”).