- a person who is opposed to, struggles against, or competes with another; opponent; adversary.
- the adversary of the hero or protagonist of a drama or other literary work: Iago is the antagonist of Othello.
- Physiology. a muscle that acts in opposition to another.Compare agonist(def 3).
- Dentistry. a tooth in one jaw that articulates during mastication or occlusion with a tooth in the opposing jaw.
- Pharmacology. a drug that counteracts the effects of another drug.
- an opponent or adversary, as in a contest, drama, sporting event, etc
- any muscle that opposes the action of anotherCompare agonist (def. 1)
- a drug that counteracts the effects of another drugCompare synergist (def. 1)
1590s, from French antagoniste (16c.) or directly from Late Latin antagonista, from Greek antagonistes “competitor, opponent, rival,” agent noun from antagonizesthai “to struggle against, oppose, be a rival,” from anti- “against” (see anti-) + agonizesthai “to contend for a prize,” from agon “contest” (see agony). Originally in battle or sport, extended 1620s to any sphere of human activity.
- Something, such as a muscle, disease, or physiological process, that neutralizes or impedes the action or effect of another.
- A muscle that opposes the action of another muscle, as by relaxing while the other one contracts, thereby producing smooth, coordinated movement.
- A chemical substance, such as a drug, that interferes with the physiological action of another substance, especially by combining with and blocking its nerve receptor. Compare agonist.