curdling vs thrombus

curdling

noun
  • The act by which something is curdled. 

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 curdling and thrombus occurred in a corpus of books? (source: Google Ngram Viewer )