• synonyms


noun Embryology.
  1. a rodlike cord of cells that forms the chief axial supporting structure of the body of the lower chordates, as amphioxus and the cyclostomes, and of the embryos of the vertebrates.
Show More

Origin of notochord

1840–50; noto- + chord1 (in the sense of ‘a cordlike anatomical structure’)
Related formsno·to·chord·al, adjectivesub·no·to·chord·al, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for notochord

Historical Examples

  • They have no backbone in the strict sense, but they have this notochord.

    The Outline of Science, Vol. 1 (of 4)

    J. Arthur Thomson

  • The skeleton is completely ossified and the notochord removed.

    The Elements of Geology

    William Harmon Norton

  • This structure is called the Notochord (a string down the back).

  • Nevertheless, traces of the notochord persist in the back-bone of these fishes.

  • Moreover, this rod was unsegmented, for the notochord is devoid of segmentation.

    The Origin of Vertebrates

    Walter Holbrook Gaskell

British Dictionary definitions for notochord


  1. a fibrous longitudinal rod in all embryo and some adult chordate animals, immediately above the gut, that supports the body. It is replaced in adult vertebrates by the vertebral column
Show More
Derived Formsnotochordal, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for notochord


1848, coined in English by English anatomist Sir Richard Owen (1804-1892) from chord + comb. form of Greek noton "back," from PIE *not- "buttock, back" (cf. Latin natis "buttock," sopurce of Italian, Spanish nalga, Old French nache "buttock, butt").

Show More
Online Etymology Dictionary, © 2010 Douglas Harper

notochord in Medicine


  1. A flexible rodlike structure that forms the main support of the body in the lowest chordates; a primitive backbone.
  2. A similar structure in embryos of higher vertebrates, from which the spinal column develops.
Show More
Related formsno′to•chordal adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

notochord in Science


  1. A flexible rodlike structure that forms the main support of the body in all chordates during some stage of their development. In vertebrates, the notochord develops into a true backbone in the embryonic phase. Primitive chordates, such as lancelets and tunicates, retain a notochord throughout their lives.
Show More
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.