calorific vs tropic

calorific

adj
  • Relating to or producing heat or other energy. 

  • High in calories and thus likely fattening. 

  • Relating to calories. 

tropic

adj
  • Hot and humid. 

  • Of, or relating to the tropics; tropical. 

  • Having the quality of indirectly inducing a biological or chemical change in a system or substrate. 

  • Pertaining to, involving, or of the nature of a trope or tropes. 

noun
  • Either of the two parallels of latitude 23°27′ north and south of the equator; the farthest points at which the sun can be directly overhead; the boundaries of the torrid zone or tropics. 

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