combustive vs riotous

combustive

adj
  • Of, pertaining to, caused by, or partaking in combustion. 

riotous

adj
  • Causing, inciting or taking part in a riot. 

  • Having the characteristics of a riot. 

  • Unrestrained and boisterous; degenerate or dissolute. 

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