血栓
Thrombus \Throm"bus\, n.; pl. {Thrombi}. [NL., fr. Gr. ? a lump, a clot of blood.] (Med.) (a) A clot of blood formed of a passage of a vessel and remaining at the site of coagulation. (b) A tumor produced by the escape of blood into the subcutaneous cellular tissue.
thrombus n : a blood clot formed within a blood vessel and remaining attached to its place of origin [also: {thrombi} (pl)]