antagonist Meaning, Definition & Usage

  1. noun someone who offers opposition
    resister; opposer; adversary; opponent.
  2. noun a muscle that relaxes while another contracts
    • when bending the elbow the triceps are the antagonist
  3. noun a drug that neutralizes or counteracts the effects of another drug


An*tag"o*nist noun
L. antagonista, Gr. against + combatant, champion, fr. : cf. F. antagoniste. See Antagonism.
  1. One who contends with another, especially in combat; an adversary; an opponent.
    Antagonist of Heaven's Almigthy King. Milton.
    Our antagonists in these controversies. Hooker.
  2. (Anat.) A muscle which acts in opposition to another; as a flexor, which bends a part, is the antagonist of an extensor, which extends it.
  3. (Med.) A medicine which opposes the action of another medicine or of a poison when absorbed into the blood or tissues. Syn. -- Adversary; enemy; opponent; toe; competitor. See Adversary.
An*tag"o*nist adjective
  1. Antagonistic; opposing; counteracting; as, antagonist schools of philosophy.

Webster 1913