Meaning of “opponent” - Learner’s Dictionary

opponent

noun [ C ] uk us /əˈpəʊnənt/
COMPETE

B2 someone who you compete against in a game or competition:

He beat his opponent six games to two.
DISAGREE

B2 someone who disagrees with an action or belief and tries to change it:

an opponent of slavery
a political opponent

(Definition of “opponent” from the Cambridge Learner’s Dictionary © Cambridge University Press)