pelvis vs solar plexus

pelvis

noun
  • A funnel-shaped cavity, especially such a cavity in the kidney into which urine passes towards the ureter 

  • The large compound bone structure at the base of the spine that supports the legs. It consists of hip bone, sacrum and coccyx. 

solar plexus

noun
  • A complex network of nerves and ganglia, located within the abdomen behind the stomach. 

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