opponent
1. [ noun ] someone who offers opposition
Synonyms: antagonist adversary resister opposer
Related terms: agonist person enemy dueler Luddite Antichrist withstander oppose resist oppose
2. [ noun ] (sport,games) a contestant that you are matched against
Synonyms: opposite opposition
Related terms: contestant pit
3. [ noun ] (military) an armed adversary (especially a member of an opposing military force)
Synonyms: foe enemy opposition foeman
Examples:

"a soldier must be prepared to kill his enemies"

Related terms: adversary besieger enemy military
4. [ adjective ] characterized by active hostility
Synonyms: opposing
Examples:

"opponent (or opposing) armies"

Related terms: hostile
Similar spelling:   opinion