Webster’s Revised Unabridged Dictionary · 1913
Thrombus
Throm′bus (thrŏm′bŭs), n.; pl. Thrombi (#). [NL., fr. Gr. θρόμβος 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.