(trŭnk )

[L. truncus, stem, stock, bole, trunk]

1. The body exclusive of the head and limbs. SYN: torso.
2. The main stem of a lymphatic vessel, nerve, or blood vessel.

brachiocephalic t.Innominate artery.

celiac t.Celiac artery.

costocervical t.A short branch of the subclavian artery, arising between the thyrocervical trunk and the dorsal scapular artery, and terminating by dividing into the deep cervical and superior intercostal arteries.

lumbosacral t.A short segment of nerve that includes part of the fourth lumbar spinal nerve (L4) and all of the fifth lumbar spinal nerve (L5). It courses inferiorly to join the sacral plexus.

nerve t.The main stem of a peripheral nerve.

pulmonary t.The artery that arises from the base of the right ventricle and bifurcates into the right and left pulmonary arteries. The pulmonary trunk is approx. 5 cm. long and 3 cm. in diameter. The aorta arches, from right to left, over the bifurcation of the pulmonary artery, with the ascending aorta running in front of the right pulmonary artery and the descending aorta running behind the left pulmonary artery. In the fetus, there is an arterial bypass, the ductus arteriosus, between the bifurcation of the pulmonary arch and the aortic arch.

sympathetic t.Either of the two long chains of paravertebral sympathetic ganglia, connected by sympathetic axons, and running alongside the vertebral column from the base of the skull to the tip of the coccyx. The segments include the cervical, thoracic, lumbar, and sacral/coccygeal.

thyrocervical t.A short, wide artery that branches from the first segment of the subclavian artery. Its branches include the inferior thyroid, subscapular, and superficial cervical arteries.