amphioxus

noun

am·​phi·​ox·​us ˌam(p)-fē-ˈäk-səs How to pronounce amphioxus (audio)
plural amphioxi ˌam(p)-fē-ˈäk-ˌsī How to pronounce amphioxus (audio) or amphioxuses
: any of a genus (Branchiostoma) of lancelets
broadly : lancelet

Examples of amphioxus in a Sentence

Recent Examples on the Web So, the presence of cartilage suggests that, even at this early stage of their evolution, vertebrates probably had a distinct nerve cord that produced a neural crest—something that our close relatives like the amphioxus doesn't have. John Timmer, Ars Technica, 7 July 2022 If that interpretation is correct, then that would mean yunnanozoans look a lot like an amphioxus, but have a feature that's otherwise found only in modern vertebrates. John Timmer, Ars Technica, 7 July 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'amphioxus.' 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

borrowed from New Latin, genus name, from Greek amphi- amphi- + oxýs "sharp, keen" — more at oxygen

Note: The genus name Amphioxus was introduced by the English naturalist and bookseller William Yarrell (1784-1856) in A History of British Fishes, vol. 2 (London, 1836), pp. 468-72. The name alludes to the shape of the animal: "both ends pointed," as noted under "generic characters." Yarrell was unaware that the Italian zoologist Gabriele Costa had named the same genus Branchiostoma two years earlier (in Cenni zoologici, ossia descrizione sommaria delle specie nuove di animali, Naples, 1834, p. 49); by rules of taxonomy, the name Branchiostoma hence has priority over Amphioxus.

First Known Use

1837, in the meaning defined above

Time Traveler
The first known use of amphioxus was in 1837

Dictionary Entries Near amphioxus

Cite this Entry

“Amphioxus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amphioxus. Accessed 19 Mar. 2024.

Kids Definition

amphioxus

noun
am·​phi·​ox·​us ˌam(p)-fē-ˈäk-səs How to pronounce amphioxus (audio)
plural amphioxi
-ˈäk-ˌsī
or amphioxuses

Medical Definition

amphioxus

1 of 2 noun
am·​phi·​ox·​us ˌam(p)-fē-ˈäk-səs How to pronounce amphioxus (audio)
plural amphioxi -ˌsī How to pronounce amphioxus (audio) -ˌsē How to pronounce amphioxus (audio) or amphioxuses
: a lancelet of the genus Branchiostoma
broadly : lancelet

Amphioxus

2 of 2 noun

taxonomic synonym of branchiostoma

More from Merriam-Webster on amphioxus

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