phlebothrombosis,
venous thrombosis thrombosis of a vein without prior inflammation of the vein; associated with sluggish blood flow (as in prolonged bedrest or pregnancy or surgery) or with rapid coagulation of the blood
Thrombosis is the formation of a blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel is injured, the body uses platelets and fibrin to form a blood clot to prevent blood loss. Alternatively, even when a blood vessel is not injured, blood clots may form in the body if the proper conditions present themselves.