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phlebothrombosis phleb·o·throm·bo·sis (flěb'ō-thrŏm-bō'sĭs)
Thrombosis in a vein without primary inflammation.
formation of a blood clot in a vein that is not inflamed. Inactivity, such as bed rest during convalescence, can lead to the condition, which frequently progresses to thrombophlebitis (q.v.), in which the clot adherent to the wall of the vein is accompanied by inflammation of the vessel.