adj. 25B6; adjective
a hostile attack : UNFRIENDLY, unkind, bitter, unsympathetic, malicious, vicious, rancorous, venomous; antagonistic, aggressive, confrontational, belligerent, truculent.
hostile climatic conditions : UNFAVOURABLE, adverse, bad, harsh, grim, hard, tough, inhospitable, forbidding.
they are hostile to the idea : OPPOSED, averse, antagonistic, ill-disposed, unsympathetic, antipathetic; opposing, against; informal anti, down on.
friendly, favourable.