frigid vs poikilothermic

frigid

adj
  • Very cold; lacking warmth; icy. 

  • Chilly in manner; lacking affection or zeal; impassive. 

  • Sexually unresponsive, especially of a woman. 

poikilothermic

adj
  • Having a body temperature that varies depending on the outside temperature. 

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