(thrombus) An intravascular aggregation of blood components, primarily platelets and fibrin with entrapment of cellular elements, which is attached to the vessel wall.

(thrombus) An aggregation of platelets and fibrin within the cardiovascular system.

A mass of blood that forms when blood platelets, proteins, and cells stick together. When a blood clot is attached to the wall of a blood vessel, it is called a thrombus. When it moves through the bloodstream and blocks the flow of blood in another part of the body, it is called an embolus.

An aggregation of blood factors, primarily platelets and fibrin with entrapment of cellular elements, frequently causing vascular obstruction at the point of its formation.

A blood clot is a mass of blood that forms when platelets, proteins, and cells in the blood stick together. When you get hurt, your body forms a blood clot to stop the bleeding. After the bleeding stops and healing takes place, your body usually breaks down and removes the blood clot. But sometimes the blood clots form where they shouldn't, your body makes too many blood clots or abnormal blood clots, or the blood clots don't break down like they should. These blood clots can be dangerous and may cause other health problems. Blood clots can form in, or travel to, the blood vessels in the limbs, lungs, brain, heart, and kidneys. The types of problems blood clots can cause will depend on where they are: Deep vein thrombosis (DVT) is a blood clot in a deep vein, usually in the lower leg, thigh, or pelvis. It can block a vein and cause damage to your leg.; A pulmonary embolism (PE) can happen when a DVT breaks off and travels through the bloodstream to the lungs. A PE, especially if it is large, can damage your lungs and prevent your other organs from getting enough oxygen.; Cerebral venous sinus thrombosis (CVST) is a rare blood clot in the venous sinuses in your brain. Normally the venous sinuses drain blood from your brain. CVST blocks the blood from draining and can cause a hemorrhagic stroke.; Blood clots in other parts of the body can cause problems such as an ischemic stroke, a heart attack, kidney problems, kidney failure, and pregnancy-related problems. Certain factors can raise your risk of developing blood clots: Atherosclerosis; Atrial fibrillation; Being overweight or having obesity; Cancer and cancer treatments; Certain genetic disorders; Certain surgeries; COVID-19; Diabetes; Family history of blood clots; Overweight and obesity; Pregnancy and giving birth; Serious injuries; Some medicines, including birth control pills; Smoking; Staying in one position for a long time, such as being in the hospital or taking a long car or plane ride. The symptoms for blood clots can be different, depending on where the blood clot is: In the abdomen: Abdominal pain, nausea and vomiting; In an arm or leg: Sudden or gradual pain, swelling, tenderness, and warmth; In the lungs: Shortness of breath, pain with deep breathing, rapid breathing, and increased heart rate; In the brain: Trouble speaking, vision problems, seizures, weakness on one side of the body, and sudden severe headache; In the heart: Chest pain, sweating, shortness of breath, and pain in the left arm. To find out if you have one or more blood clots, your health care provider: Will do a physical exam.; Will take your medical history, which includes asking about your symptoms.; May order blood tests, including a D-dimer test.; May order...

(thrombosis/thrombus) The formation of a blood clot in the lumen of a vessel or heart chamber.