Thromboembolism: Formation in a blood vessel of a clot (thrombus) that breaks loose and is carried by the blood stream to plug another vessel. The clot may plug a vessel in the lungs (pulmonary embolism), brain (stroke), gastrointestinal tract, kidneys, or leg. Thromboembolism is a significant cause of morbidity (disease) and mortality (death), especially in adults. Treatment may involve anticoagulants (blood thinners), aspirin, or vasodilators (drugs that relax and widen vessels).
