Clot
The medical expression is thrombus (pl. thrombi) when the clot is located at its origin. If a (part of a) clot has dislodged, moved with the blood and stuck in another blood vessel that becomes narrowed or obstructed, the clot is called an (thrombo-)embolus (pl. emboli). Clots normally originate after an injury to a blood vessel, like a wound or a heavy blow causing internal injury. The main function of a clot is to stop or limit blood loss by plugging the holes in the blood vessels, but certain diseases or situations may cause clots to form spontaneously.
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