[ad. (perh. through Fr. antagoniste, 16th c. in Litt.) L. antagōnista (in Jerome), ad. Gr. ἀνταγωνιστ-ής opponent, rival, n. of agent f. ἀνταγωνίζ-εσθαι: see ANTAGONIZE.]
1. One who contends with another in an athletic contest, a battle, or struggle for the mastery; an opponent, an adversary.
1599. B. Jonson, Cynthia’s Rev., V. ii. Your antagonist, or player against you.
1623. Cockeram, Antagonist, an enemy.
1667. Milton, P. L., X. 387. Satan … Antagonist of Heaven’s Almightie King.
1790. Burke, Fr. Rev., 246. He that wrestles with us strengthens our nerves, and sharpens our skill. Our antagonist is our helper.
1855. Prescott, Philip II., I. ii. (1857), 31. Philip ran the first course. His antagonist was the Count Mansfeldt, a Flemish captain of great renown.
2. An opponent in any sphere of human action, as politics, controversy, etc.
1626. Pory, in Ellis, Orig. Lett., II. 333, III. 247. Potter and Godfrey, antagonistes to the Pope’s supremacy here.
1628. Prynne, Cens. Cozens, 14. Marke what good vse our Antagonist makes of this conclusion.
1706. Phillips, Antagonist … one that in Disputation or Arguing opposes another.
1831. Brewster, Newton (1855), II. xxiii. 307. This answer of Sir Isaac’s … called into the field a fresh antagonist.
3. An impersonal agent acting in opposition.
1711. Addison, Spect., No. 10, ¶ 3. A well written Book compared with its Rivals and Antagonists, is like Moses’s Serpent.
1794. Sullivan, View Nat., II. 117. Fire and air act as antagonists in boiling.
1836. J. Gilbert, Chr. Atonem., v. (1852), 136. Justice and mercy ought by no account to be considered as antagonists.
4. Phys. A muscle that counteracts another, contracting while the opposite one relaxes, and conversely.
1706. Phillips, Antagonista or Antagonist (in Anat.) is taken for a Muscle of an opposite Situation or contrary Quality.
1751. Chambers, Cycl., s.v., We have some solitary muscles, without any Antagonists.
1880. Syd. Soc. Lex., s.v., The flexor muscles are the antagonists of the extensors.
5. Used attrib. as sb. in apposition, or adj.: = ANTAGONISTIC.
1671. Milton, Samson, 1628. None daring to appear antagonist.
1777. Priestley, Phil. Necess., § 4. 31. A limb is kept motionless by the equal action of antagonist muscles.
1789. T. Jefferson, Writ. (1859), II. 588. The antagonist nation.
1830. Coleridge, Ch. & State, 141. Antagonist forces are necessarily of the same kind.
1830. Sir J. Herschel, Stud. Nat. Phil., 189. The quality of opacity is not a contrary or antagonist quality to that of transparency.
