hostile

characterized by enmity or ill will; "a hostile nation"; "a hostile remark"; "hostile actions"

not belonging to your own country''s forces or those of an ally; "hostile naval and air forces"

impossible to bring into friendly accord; "hostile factions"

very unfavorable to life or growth; "a hostile climate"; "an uncongenial atmosphere"; "an uncongenial soil"; "the unfriendly environment at high altitudes"

unsolicited and resisted by the management of the target company ( used of attempts to buy or take control of a business); "hostile takeover"; "hostile tender offer"; "hostile bid"

troops belonging to the enemy''s military forces; "the platoon ran into a pack of hostiles"