- a condition in which a blood clot forms in a vein deep beneath the skin, typically in the leg or pelvic area: Immobility and lack of exercise are risk factors for deep-vein thrombosis.
- a blood clot in a vein deep beneath the skin.
- a blood clot in one of the major veins, usually in the legs or pelvis; can be caused by prolonged sitting in the same position, as on long-haul air flights
