pedunculus pe·dun·cu·lus (pĭ-dŭng'kyə-ləs)
n. pl. pe·dun·cu·li (-lī')
An anatomical stalk or stem, such as the stalklike base to which a tumor is attached to normal tissue.
Any of several stalklike connecting structures in the brain, composed either of white matter or of white and gray matter. Also called peduncle.