Could you tell me what an embolism is?

Embolism: A blood clot or air in the veins that travels to the lungs and can cause death.

Blockage of blood: Embolism is something that blocks proper flow of blood in the body. An embolism is usually a blood clot that can forms in your veins or arteries that can lodge in dangerous places in your circulatory system. Venous embolisms can cause catastrophic breathing problems. Air, fat and a few other things can also be a type of embolism that blocks blood flow.