What is the difference between a thrombus an embolus and a thromboembolism?

A thrombus is a blood clot that forms in a blood vessel, obstructing blood flow at its site of formation. An embolus is a fragment of a thrombus or other material that travels through the bloodstream and can lodge in a blood vessel, causing a blockage elsewhere. Thromboembolism refers to the condition where a thrombus forms and then an embolus breaks off from it, leading to a blockage in a distant vessel, which can result in serious complications like stroke or pulmonary embolism.