acrid vs thermic

acrid

adj
  • Causing heat and irritation. 

  • Caustic; bitter; bitterly irritating. 

  • Sharp and harsh, or bitter and not to the taste. 

thermic

adj
  • Of, related to, or associated with heat; thermal. 

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