em·bo·lus / ˈembələs/ • n. (pl. -li / -ˌlī; -ˌlē/ ) a blood clot, air bubble, piece of fatty deposit, or other object that has been carried in the bloodstream to lodge in a vessel and cause an embolism.

embolus (em-bŏ-lŭs) n. (pl. emboli) material, such as a blood clot, fat, air, amniotic fluid, or a foreign body, that is carried by the blood from one point in the circulation to lodge at another point (see embolism).