from The American Heritage® Dictionary of the English Language, 4th Edition
- n. One who opposes and contends against another; an adversary.
- n. The principal character in opposition to the protagonist or hero of a narrative or drama.
- n. Physiology A muscle that counteracts the action of another muscle, the agonist.
- n. Biochemistry A chemical substance that interferes with the physiological action of another, especially by combining with and blocking its nerve receptor.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An opponent or enemy.
- n. One who antagonizes or stirs.
- n. A chemical that binds to a receptor but does not produce a physiological response, blocking the action of agonist chemicals.
- n. The main character or force opposing the protagonist in a literary work or drama.
from the GNU version of the Collaborative International Dictionary of English
- n. One who contends with another, especially in combat; an adversary; an opponent.
- n. A muscle which acts in opposition to another.
- n. A medicine which opposes the action of another medicine or of a poison when absorbed into the blood or tissues.
- adj. Antagonistic; opposing; counteracting.
from The Century Dictionary and Cyclopedia
- n. One who contends with another in combat or in argument; an opponent; a competitor; an adversary.
- n. In anatomy, a muscle which acts in opposition to another: as, a flexor, which bends a part, is the antagonist of an extensor, which extends it.
- Counteracting; opposing; combating: as, antagonist forces; an antagonist muscle.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a drug that neutralizes or counteracts the effects of another drug
- n. someone who offers opposition
- n. a muscle that relaxes while another contracts
From Latin antagonista, from Ancient Greek ἀνταγωνιστής ("opponent") (ἀντί (anti, "against") + ἀγωνιστής (agōnistēs, "a combatant, pleader, actor")), from ἀνταγωνίζεσθαι ("antagonize"). (Wiktionary)