antagonist


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Related to antagonist: protagonist, antagonist drug, Dopamine antagonist

antagonist

1. any muscle that opposes the action of another
2. a drug that counteracts the effects of another drug

antagonist

[an′tag·ə‚nist]
(biochemistry)
A molecule that bears sufficient structural similarity to a second molecule to compete with that molecule for binding sites on a third molecule.
(pharmacology)
A drug or other chemical substance capable of reducing the physiological activity of another chemical substance; refers especially to a drug that opposes the action of a drug or other chemical substance on the nervous system by combining with and blocking the nerve receptor.
(physiology)
A muscle that contracts with, and limits the action of, another muscle, called an agonist, with which it is paired.
References in classic literature ?
What greatly strengthens such a suspicion is the fact that this controversy between two ill-matched antagonists --at a period, moreover, laud it as we may, when personal influence had far more weight than now--remained for years undecided, and came to a close only with the death of the party occupying the disputed soil.
I say that, on that day, each knight ran three courses, and cast to the ground three antagonists.
Bennet, he offered himself as his antagonist at backgammon.
He exerted his physical powers on the present occasion, with much discretion; and, as he had taken his antagonist at a great disadvantage, the struggle resulted very soon in Benjamin getting the magistrate fixed in a posture somewhat similar to his own, and manfully placed face to face.
As little does he think how near together he and his antagonist have suffered in the fortunes of two sisters, and his antagonist, who knows it now, is not the man to tell him.
But I had reckoned without a just appreciation either of the cunning of my immediate antagonist or the swiftness with which his fellows were covering the distance which had separated them from me.
Halting only for the brief instant that was required to wrench my sword from the carcass of my late antagonist, I sprang across the chamber to the blank wall beyond, through which the thern had attempted to pass.
Presently, after moving, he leaned back and gazed with a curious abstraction at his antagonist.
Had Tarzan been a full-grown bull ape of the species of his tribe he would have been more than a match for the gorilla, but being only a little English boy, though enormously muscular for such, he stood no chance against his cruel antagonist.
And in the air are no streets, no channels, no point where one can say of an antagonist, "If he wants to reach my capital he must come by here.
Yet, if he could not see his antagonist, neither could his antagonist now see him.
He was battered and bruised and covered with blood from Numa and dirt from the trail, yet not for an instant did he lessen the ferocity of his mad attack nor his grim hold upon the back of his antagonist.