thoracic duct noun
: the main trunk of the system of lymphatic vessels that lies along the front of the spinal column, extends from a dilatation behind the aorta and opposite the second lumbar vertebra up through the thorax where it turns to the left and opens into the left subclavian vein, and receives chyle from the intestine and lymph from the abdomen, the lower limbs, and the entire left side of the body—called also left lymphatic duct
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