adversary

 
Pronunciation: /ˈadvəs(ə)ri/

noun (plural adversaries)

  • one’s opponent in a contest, conflict, or dispute: Davis beat his old adversary in the quarter-finals

adjective

Pronunciation: /ˈadvəs(ə)ri, adˈvəːsəri/
  • another term for adversarial. the confrontations of adversary politics

Origin:

Middle English: from Old French adversarie, from Latin adversarius 'opposed, opponent', from adversus (see adverse)