n.[C]

1. 敌手，对手
   The knight defeated each antagonist.

   那位骑士打败了每一个敌手。

2. 对立者，反对者
3. 【解】对抗肌
4. 【药】对抗药

n.

1. a person who actively opposes or is hostile towards someone or something.
2. Biochemistry  a substance which interferes with the physiological action of another.
3. Anatomy  a muscle whose action counteracts that of another muscle.