Embolism

In medicine, an embolism occurs when an object (the embolus) or objects (emboli) migrate from one part of the body (through the circulation) and cause(s) a blockage (occlusion) of a blood vessel in another part of the body.

This can be contrasted with a "thrombus" which is an occlusion of a blood vessel by a clot formed at the site of the occlusion, rather than carried from elsewhere.

Blood clots form the most common embolic material by far: other possible embolic materials include fat globules, air bubbles, septic emboli (containing pus[?] and bacteria), or amniotic fluid.

Emboli often have more serious consequences when they occur in the so-called "end-circulation": areas of the body that have no redundant blood supply, such as the brain, heart, and lungs.