thromboid vs thrombus

thromboid

adj
  • Resembling a thrombus 

noun
  • Synonym of thrombus 

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