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agonist

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noun ag·o·nist \ˈa-gə-nist\

Definition of agonist

  1. 1 :  one that is engaged in a struggle

  2. 2 [from antagonist] a :  a muscle that is controlled by the action of an antagonist with which it is paired b :  a chemical substance capable of combining with a specific receptor on a cell and initiating the same reaction or activity typically produced by the binding endogenous substance <dopaminergic agonists> — compare antagonist 2b



Origin and Etymology of agonist

Late Latin agonista competitor, from Greek agōnistēs, from agōnizesthai to contend, from agōn


First Known Use: circa 1623


Medical Dictionary

agonist

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noun ag·o·nist \ˈag-ə-nəst\

Medical Definition of agonist

  1. 1:  a muscle that on contracting is automatically checked and controlled by the opposing simultaneous contraction of another muscle—called also agonist muscle, prime mover; compare antagonist a, synergist 2

  2. 2:  a chemical substance (as a drug) capable of combining with a receptor on a cell and initiating the same reaction or activity typically produced by the binding of an endogenous substance <binding of adrenergic agonists>—compare antagonist b




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