agonist

ag·o·nist

noun \ˈa-gə-nist\

Definition of AGONIST

1

: one that is engaged in a struggle

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 of AGONIST

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

First Known Use: circa 1623