hostile

Very unfavorable to life or growth.

“a hostile climate”

Characterized by enmity or ill will.

“a hostile nation”

“a hostile remark”

Impossible to bring into friendly accord.

“hostile factions”

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”

Troops belonging to the enemy's military forces.

“the platoon ran into a pack of hostiles”

Not belonging to your own country's forces or those of an ally.

“hostile naval and air forces”