dissident vs oppositional

dissident

adj
  • In a manner that disagrees; dissenting; discordant. 

noun
  • One who disagrees or dissents; one who separates from the established religion. 

  • Sometimes Dissident: in the kingdom of Poland, the name for Christians not part of the Roman Catholic Church. 

  • A person who formally opposes the current political structure, the political group in power, the policies of the political group in power, or current laws. 

oppositional

adj
  • Of, pertaining to, or exhibiting opposition 

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