agonist

 
Pronunciation: /ˈagənɪst/

noun

  • 1 Biochemistry a substance which initiates a physiological response when combined with a receptor. Compare with antagonist.
  • 2 Anatomy a muscle whose contraction moves a part of the body directly: [as modifier]: there is a failure to select the right agonist musclesCompare with antagonist.

Derivatives

agonism

noun

Origin:

early 20th century: from Greek agōnistēs 'contestant' (a sense reflected in English in the early 17th century), from agōn 'contest'