Meaning of ANTAGONIST in English

ANTAGONIST

n.

Pronunciation: -nist

Function: noun

Date: 1575

1 : one that contends with or opposes another : ADVERSARY , OPPONENT

2 : an agent of physiological antagonism: as a : a muscle that contracts with and limits the action of an agonist with which it is paired ― called also antagonistic muscle b : a chemical that acts within the body to reduce the physiological activity of another chemical substance (as an opiate) especially : one that opposes the action on the nervous system of a drug or a substance occurring naturally in the body by combining with and blocking its nervous receptor ― compare AGONIST 2b

Merriam Webster Collegiate English Dictionary.      Merriam Webster - Энциклопедический словарь английского языка.