bloodshed vs thrombus

bloodshed

noun
  • The shedding or spilling of blood. 

  • A slaughter; destruction of life, notably on a large scale. 

thrombus

noun
  • A blood clot formed from platelets and other elements that forms in a blood vessel in a living organism, and causes thrombosis or obstruction of the vessel at its point of formation or travel to other areas of the body. 

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