• synonyms

jawless fish

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  1. cyclostome.

Origin of jawless fish

First recorded in 1965–70; jaw1 + -less
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
jawless fish in Science

jawless fish

  1. Any of various primitive fish of the class Agnatha that lack jaws. Living jawless fish (lampreys and hagfish) have a long, cylindrical body and a cartilaginous skeleton. The numerous extinct species were often heavily armored and are among the earliest vertebrate fossils known. Jawless fish occupy an intermediate evolutionary position between primitive chordates and jawed fish. Also called agnathan See more at cyclostome. Compare bony fish cartilaginous fish.
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