2 definitions found

From WordNet (r) 2.0 [wn]:

agonist

noun

1: the principal character in a work of fiction [syn: {protagonist}]

2: someone involved in a contest or battle (as in an agon) [ant: {adversary}]

3: a muscle that contracts while another relaxes; "when bending the elbow the biceps are the agonist"

4: (biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction

From The Collaborative International Dictionary of English v.0.44 [gcide]:

Agonist \Ag"o*nist\, noun [Gr. ?.] One who contends for the prize in public games. [R.]
  Definitions retrieved from local copies of the freely distributed DICT client/server software and databases. Click here for database copyright information. -KM