Borrowed from Latin oppōnēns, present active participle of oppōnō ("I oppose").

• IPA: /əˈpəʊnənt/

opponent (plural opponents)

1. One who opposes another; one who works or takes a position against someone or something; one who attempts to stop the progress of someone or something.

   The person who ran against her in the last election proved to be a formidable opponent.

   During the crackdown, many opponents of the regime were arrested.

   1. One who opposes another physically (in a fight, sport, game, or competition).
      • 1720, Alexander Pope, The Iliad of Homer, London: Bernard Lintott, Volume 6, “Observations on the Twenty-Third Book,” no. 39, p. 136,

        In the Chariot-Race Achilles is represented as being able to conquer every Opponent […]

      • 1819 December 20 (indicated as 1820), Walter Scott, “CHAPTER 11 ↗”, in Ivanhoe; a Romance. […], volume (please specify |volume=I to III), Edinburgh: […] Archibald Constable and Co.; London: Hurst, Robinson, and Co. […], →OCLC ↗:

        […] he slid his right hand down to his left, and with the full swing of the weapon struck his opponent on the left side of the head, who instantly measured his length upon the green sward.

      • 1958, Graham Greene, Our Man in Havana‎, New York: Pocket Books, published 1974, Part 5, Chapter 5, p. 196:

        […] it is possible for a good [draughts] player to defeat an opponent without capturing his pieces.

   2. One who opposes another in words (in a dispute, argument or controversy).
      • 1847, Charlotte Brontë, chapter 4, in Jane Eyre‎:

        “What more have you to say?” she asked, rather in the tone in which a person might address an opponent of adult age than such as is ordinarily used to a child.

   3. One who is opposed or objects (to a policy, course of action or set of ideas).

      She was a dedicated opponent of the death penalty.

      • 1652, Peter Heylin, Cosmographie‎, London: Henry Seile, Book 1, Part 20, p. 205:

        Their Oath is to maintain the Romish-Catholick Religion, and persecute all Opponents to it.

      • 1853, Elizabeth Gaskell, chapter 1, in Cranford‎:

        My own friends had been among the bitterest opponents of any proposal to visit the Captain and his daughters, only twelve months before; and now he was even admitted in the tabooed hours before twelve.

   4. (historical) The participant who opens an academic debate by putting forward objections to a theological or philosophical thesis.
      • 1679, William Penn, An Address to Protestants‎, London, Part 2, p. 77:

        […] by the many Disputes that rise from hence, Mens Wits were confounded with their matters, Truth was lost & Brotherhood destroyed: thus the Devil acted the Part both of Opponent and Defendant, and managed the Passions of both Parties to his End, which was DISCORD.

      • 1700, John Sergeant, Transnatural Philosophy‎, London, Book 3, Chapter 1, p. 276:

        […] this untoward Method allows him who is the Respondent, to prevaricate from his Duty, and turn Opponent: Which confounds those two Offices, and perverts all the Laws of Reasoning or Discoursing.

• adversary
• antagonist

• (antonym(s) of “one who opposes”): supporter, proponent, advocate
• (antonym(s) of “person who opens an academic debate”): respondent

• German: Gegner, Gegnerin
• Russian: проти́вник
• Spanish: oponente, antagonista

• French: adversaire
• Russian: проти́вник
• Spanish: oponente, contrincante

• Spanish: adversario

• Spanish: opositor

opponent

1. (obsolete) Opposing; adverse; antagonistic.
   • 1726, Elijah Fenton, transl., The Odyssey of Homer, Translated from the Greek by Alexander Pope‎, London, published 1760, Volume 4, Book 19, lines 524-525, p. 44:

     Young Ithacus advanc’d, defies the foe,
     Poising his lifted lance in act to throw:
     The savage renders vain the wound decreed,
     And springs impetuous with opponent speed!

   • 1792, Thomas Holcroft, Anna St. Ives‎, London: Shepperson and Reynolds, Volume 4, Letter 64, p. 53:

     The reasons you have urged are indeed weighty: yet they have never made an impression so deep upon my mind, as not to take flight, and leave their opponent arguments in some sort the victors.

   • 1828, Stephen Drew, Principles of Self-Knowledge‎, London: Longman, Volume 2, Section 23, p. 24:

     Let it not be supposed, that by “catholic,” I mean to designate men who are lax in their principles, and alike indifferent to all religious systems. On the contrary, they are more earnestly attached to truth, and more opponent to sin than others […]

2. (obsolete) Situated in front; opposite.
   • a. 1749 (date written), James Thomson, “Spring”, in The Seasons, London: […] A[ndrew] Millar, and sold by Thomas Cadell, […], published 1768, →OCLC ↗, page 33 ↗:

     Her sympathizing Lover takes his Stand
     High on th’ opponent Bank […]

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