adversary的基本意思是辩论或者战斗中的“敌手; 对手”,可指怀有敌对思想,也可指采取敌对行动,一般较难对付。

His principal adversary was David Lloyd George. 他的主要对手是戴维·劳埃德·乔治。
Which school is our adversary in this week's football game? 本周足球赛中我们的对手是哪个学校？
Now the Danube confronts a modern adversary—pollution.多瑙河如今面对着一个现代的敌人——污染。
You've come up against a powerful adversary.你遇到了一个强大的敌人。
He saw her as his main adversary within the company.他将她视为公司中主要的对手。
Of the two potential adversaries,Britain was not yet ready to commit herself. 这两个潜在敌手之中,英国还不准备作出明确的承诺。

adversary, antagonist, enemy, foe, opponent
参见foe条。