Clot: When a blood vessel is injured, the damaged cells in the vessel wall send out chemical signals. These signals cause clots that slow or stop bleeding. Link Blood clots are made up of little particles called platelets and a meshwork of protein strands, called fibrin. Link
Thrombus: A thrombus is a blood clot in a blood vessel. Link Thrombosis is the formation of a blood clot (thrombus) inside one of your blood vessels or a chamber of your heart. Clots can block blood flow in your blood vessels or break free and travel elsewhere in your body. If a clot gets stuck in a critical location like your lungs or brain, it can disrupt blood flow to that organ and result in a life-threatening emergency. Link
Embolus: An embolus is a particle or mass that flows through the bloodstream. A thrombus is a blood clot in a blood vessel. If a thrombus breaks off, it can become an embolus. Link
Plaque: Plaque is made up of deposits of fatty substances, cholesterol, cellular waste products, calcium, and fibrin. As it builds up in the arteries, the artery walls become thickened and stiff. Link