cephalochordate

noun

ceph·​a·​lo·​chor·​date ˌse-fə-lō-ˈkȯr-ˌdāt 

-dət

plural cephalochordates

: an animal of the subphylum Cephalochordata : lancelet

Although cephalochordates had achieved the primary characters of chordates—notochord, dorsal hollow nerve cord, and pharyngeal gill slits—as well as a postanal tail and segmental muscles throughout the trunk and tail, they lack many other features that characterize vertebrates.

—Robert L. Carroll, Patterns and Processes of Vertebrate Evolution, 1997

cephalochordate adjective

Word History

First Known Use

1904, in the meaning defined above

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