vis ma·jor 
(vĭs mājər)
(vĭs mājər)n. pl. vi·res ma·jo·res (vī′rēz mə-jôrēz, -jŏr-)
Law
Law
An overwhelming, unanticipated, and unpreventable event, usually caused by a natural force, the occurrence of which may exempt a party from performing the obligations of a contract. Also called force majeure.
[Latin vīs māior : vīs, force + māior, greater.]