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”

very unfriendly

• “a hostile attitude”

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”

marked by features that oppose constructive treatment or development

• “not able to accomplish much in such a hostile environment”

used of attempts to buy or take control of a business

• “hostile takeover”
• “hostile tender offer”