\No"to*chord\, n. [Gr. ? the back + E. chord.] (Anat.)
An elastic cartilagelike rod which is developed beneath the
medullary groove in the vertebrate embryo, and constitutes
the primitive axial skeleton around which the centra of the
vertebr[ae] and the posterior part of the base of the skull
are developed; the chorda dorsalis. See Illust. of
{Ectoderm}.