denialist vs turncoat

denialist

noun
  • One who denies an assertion in a controversial debate. 

adj
  • Relating to denial in a controversial debate. 

turncoat

noun
  • A traitor; one who turns against a previous affiliation or allegiance. 

verb
  • To act as a turncoat; to betray 

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