From qarach; a bald spot (on the back of the head); figuratively, a threadbare spot (on the back side of the cloth) -- bald head, bare within.
see HEBREW qarach
H7146. qarachath
קָרַחַת noun feminine baldness of head; — absolute ׳ק Leviticus 13:42 a; suffix קָרַחְתּוֺ 13:42 +; — baldness of head (always opposed to גַּבַּחַת baldness of forehead), 13:42 (twice in verse); 13:43, 55.