opponent

Etymology

Borrowed from Latin oppōnēns (“opposing”), present active participle of oppōnō (“I oppose”).

noun

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.
   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 […]
      […] it is possible for a good [draughts] player to defeat an opponent without capturing his pieces. 1958, Graham Greene, Our Man in Havana, New York: Pocket Books, published 1974, Part 5, Chapter 5, p. 196
   2. One who opposes another in words (in a dispute, argument or controversy).
      It is easier to confound than to convince an opponent; the former may be effected by a turn that has more happiness than truth in it. 1777, Hannah More, “Thoughts on Conversation”, in Essays on Various Subjects, London: J. Wilkie and T. Cadell, page 54
      “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. 1847, Charlotte Brontë, chapter 4, in Jane Eyre
   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.
      Their Oath is to maintain the Romish-Catholick Religion, and persecute all Opponents to it. 1652, Peter Heylin, Cosmographie, London: Henry Seile, Book 1, Part 20, p. 205
      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. 1853, Elizabeth Gaskell, chapter 1, in Cranford
   4. (historical) The participant who opens an academic debate by putting forward objections to a theological or philosophical thesis.
      We make the argument appere slender, when we receiue it laughyngly, and declare by wordes, euen at the first, that it is nothyng to the purpose, and so abashe the opponent. 1551, Thomas Wilson, “The maner of confutacion twoo waies considered”, in The Rule of Reason, conteinyng the Arte of Logique, London
      […] diuinitie disputations, in all which those learned opponents, respondents, & moderators, quited themselues like themselues, sharplie and soundlie, besides all other solemne sermons & lectures. 1587, Raphael Holinshed et al., “The Continvation of the chronicles of England from the yeare of our Lord 1576, to this present yeare 1586, &c.”, in The First and Second Volumes of Chronicles, London, page 1355
      […] 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. 1679, William Penn, An Address to Protestants, London, Part 2, p. 77
      […] 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. 1700, John Sergeant, Transnatural Philosophy, London, Book 3, Chapter 1, p. 276

adj

1. (obsolete) Opposing; adverse; antagonistic.
   […] we are to consider enemies as men opponent to peace and justice, and to these they are by warrs to be reduced; And no other ends in the pursuite of enemies by sword and hostile Acts are to be sought for […] 1647, Francis Bland, The Souldiers March to Salvation, York, page 25
   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! 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
   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. 1792, Thomas Holcroft, Anna St. Ives, London: Shepperson and Reynolds, Volume 4, Letter 64, p. 53
   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 […] 1828, Stephen Drew, Principles of Self-Knowledge, London: Longman, Volume 2, Section 23, p. 24
2. (obsolete) Situated in front; opposite.