hostility (n.)
early 15c., "hostile action," from Middle French hostilité "enmity" (15c.), or directly from Late Latin hostilitatem (nominative hostilitas) "enmity," from Latin hostilis "inimical," from hostis, in earlier use "a stranger, foreigner," in classical use "an enemy," from PIE root *ghos-ti- "stranger, guest, host." Hostilities in the sense of "warfare" attested from 1610s.