secede vs tergiversate

secede

verb
  • To split from or to withdraw from membership of a political union, an alliance or an organisation. 

  • To split or to withdraw one or more constituent entities from membership of a political union, an alliance or an organisation. 

tergiversate

verb
  • To change sides or affiliation; to apostatize. 

  • To evade, to equivocate using subterfuge; to obfuscate in a deliberate manner. 

  • To flee by turning one's back. 

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