Where does “bascule” come from?

bascule (French) comes from French bacule, from Old French bacul, 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.

bascule (French): first-person singular present indicative of...