thorax vs torso

thorax

noun
  • The region of the mammalian body between the neck and abdomen as well as the cavity containing the heart and lungs. 

  • The middle of three distinct divisions in an insect, crustacean or arachnid body to which the legs are attached. 

torso

noun
  • The main part of the (human) body that extends from the neck to the groin, excluding the head and limbs. 

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