notochord

noun

no·​to·​chord ˈnō-tə-ˌkȯrd How to pronounce notochord (audio)
: a longitudinal flexible rod of cells that in the lowest chordates (such as a lancelet or a lamprey) and in the embryos of the higher vertebrates forms the supporting axis of the body
notochordal adjective

Examples of notochord in a Sentence

Recent Examples on the Web Chordates share several common features, but the most notable is a flexible, supportive rod structure, or notochord, that runs down the animal’s length. Elizabeth Rayne, Ars Technica, 16 July 2023 In 2016, researchers claimed to have identified a pale gut-like structure as a notochord, a primitive spine, signaling a vertebrate affinity. Jamie Dickman, Popular Science, 17 Apr. 2023 The very first step of this sequence is represented by chordates, or creatures with a notochord supporting their body. John Long, Discover Magazine, 12 June 2014 The tailfin and notochord — basically the sturgeon’s spine — is pulled out. oregonlive, 25 Aug. 2021 But that streak is important—it’s a notochord, or a precursor of our spinal column that marks Pikaia as one of the earliest relatives of vertebrates. Riley Black, Smithsonian Magazine, 10 Dec. 2020 But several fossils revealed that the band bore the hallmark traits of a notochord, the rubbery tube surrounding some primitive vertebrates’ spinal cords. Michael Greshko, National Geographic, 16 Mar. 2016 Instead what’s called a notochord, a flexible rod of tissue, extends along hagfish backs. Susan Milius, WIRED, 2 Mar. 2011

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'notochord.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Greek nōton, nōtos back + Latin chorda cord — more at cord

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of notochord was in 1848

Dictionary Entries Near notochord

Cite this Entry

“Notochord.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/notochord. Accessed 14 Apr. 2024.

Kids Definition

notochord

noun
no·​to·​chord ˈnōt-ə-ˌkȯ(ə)rd How to pronounce notochord (audio)
: a flexible supporting rod of cells that exists in the embryos of all chordates, remains in the adults of some primitive forms (as lancelets and lampreys), and is replaced by the backbone in most vertebrates

Medical Definition

notochord

noun
no·​to·​chord ˈnōt-ə-ˌkȯ(ə)rd How to pronounce notochord (audio)
: a longitudinal flexible rod of cells that in the lowest chordates (as a lancelet or a lamprey) and in the embryos of the higher vertebrates forms the supporting axis of the body, that is almost obliterated in the adult of the higher vertebrates as the bodies of the vertebrae develop, and that arises as an outgrowth from the dorsal lip of the blastopore extending forward between epiblast and hypoblast in the middorsal line
notochordal adjective

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