The Collaborative International Dictionary of English v.0.48:

Antagony \An*tag"o*ny\, n. [Gr. ?; 'anti` + ? contest: cf. F.
   (16th century) antagonie. See Antagonism.]
   Contest; opposition; antagonism. [Obs.]
   [1913 Webster]

         Antagony that is between Christ and Belial. --Milton.
   [1913 Webster]