Definition of plaintiff in US English:



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

    Compare with defendant
    • ‘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.’
    • ‘The defendants negligently told the plaintiffs that X was much wealthier than in fact he was.’
    • ‘The plaintiffs sued the defendant alleging that he had been negligent in a number of ways.’
    • ‘Several years later the plaintiff gave the defendant notice to quit under the lease agreement.’
    litigator, opponent in law, opponent, contestant, contender, disputant, claimant, complainant, petitioner, appellant, respondent, party, interest, defendant, accused
    View synonyms


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.