sûr, -e, sure, certain.
sûreté, f., security.
surlendemain, on the third day; m., the next day but one.
surmonter, to overcome.
surmonté, -e, crowned, surmounted.
surprendre, to surprise.
surpris, -e, surprised.
surtout, especially.
surveiller, to oversee, watch over.
survenir, to happen or come unexpectedly.