S / suspensūra
noun

suspensūra

gen. suspensūrae · gender feminine · decl. 1st
an arching; vaulting; arched work
an arching or vaulting, arched work, an arch: balneorum, Sen. Ep. 90, 25; cf. caldariorum, Vitr. 5, 10: cellarum, Pall. 1, 40, 2.