opposition vs rival

opposition

noun
  • A position in which the player on the move must yield with his king allowing his opponent to advance with his own king. 

  • The difference of quantity or quality between two propositions having the same subject and predicate. 

  • A political party or movement opposed to the party or government in power. 

  • In United States intellectual property law, a proceeding in which an interested party seeks to prevent the registration of a trademark or patent. 

  • The action of opposing or of being in conflict. 

  • The apparent relative position of two celestial bodies when one is at an angle of 180 degrees from the other as seen from the Earth. 

  • An opposite or contrasting position. 

rival

noun
  • A competitor (person, team, company, etc.) with the same goal as another, or striving to attain the same thing. Defeating a rival may be a primary or necessary goal of a competitor. 

  • Someone or something with similar claims of quality or distinction as another. 

adj
  • Having the same pretensions or claims; standing in competition for superiority. 

verb
  • To be equal to, or match, or to surpass another. 

  • To oppose or compete with. 

  • To strive to equal or excel; to emulate. 

How often have the words opposition and rival occurred in a corpus of books? (source: Google Ngram Viewer )