Simple Definition of opponent
: a person, team, group, etc., that is competing against another in a contest
: a person, group, etc., that is against something (such as an action, law, or system) : someone or something that does not want something to exist, be done, etc.
Examples of opponent in a sentence
She is a formidable opponent in the race for senator.
The team's opponents have not lost a game this season.
He knocked out his opponent in the third round.
Origin and Etymology of opponent
Latin opponent-, opponens, present participle of opponere
First Known Use: 1560
OPPONENT Defined for Kids
Definition of opponent for Students
: a person or thing that takes an opposite position in a contest, fight, or controversy
Medical Definition of opponent
: a muscle that opposes or counteracts and limits the action of another
Seen and Heard
What made you want to look up opponent? Please tell us where you read or heard it (including the quote, if possible).