Word Study
notochord
CIDE DICTIONARY
notochord, n. [Gr. nw^ton the back + E. chord.].
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 vertebræ and the posterior part of the base of the skull are developed; the chorda dorsalis . See Illust. of Ectoderm. [1913 Webster]
OXFORD DICTIONARY
notochord, n. a cartilaginous skeletal rod supporting the body in all embryo and some adult chordate animals.
Etymology
Gk noton back + CHORD(2)
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