Definition of plaintiff in US English:



  • A person who brings a case against another in a court of law.

    ‘the plaintiff commenced an action for damages’
    Compare with defendant
    • ‘Several years later the plaintiff gave the defendant notice to quit under the lease agreement.’
    • ‘The plaintiffs sued the defendant alleging that he had been negligent in a number of ways.’
    • ‘The defendants negligently told the plaintiffs that X was much wealthier than in fact he was.’
    • ‘The plaintiffs engaged the defendants as their solicitors to act for them.’
    • ‘Three defendants were each found liable to the plaintiff in a personal injuries case.’
    litigator, opponent in law, opponent, contestant, contender, disputant, claimant, complainant, petitioner, appellant, respondent, party, interest, defendant, accused
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Late Middle English: from Old French plaintif ‘plaintive’ (used as a noun). The -f ending has come down through Law French; the word was originally the same as plaintive.