femoral vein, a large vein in the thigh that is a continuation of the popliteal vein and that accompanies the femoral artery in the proximal two thirds of the thigh. Its distal portion lies lateral to the artery, and its proximal portion lies deeper to the artery. Near its termination, it is joined by the great saphenous vein. At the inguinal ligament it becomes the external iliac vein.
