Where does “cul” come from?

cul (French) comes from Middle French cul, from Old French cul, from Latin cūlus, from Proto-Celtic kūlos, from Proto-Indo-European ḱuH-ló-, from Proto-Indo-European (s)kewH- — to cover, bedeck; cover.

cul (French): butt, bum, ass, arse; anus; arsehole; asshole;...