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agnathan

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noun ag·na·than \ ˈag-nə-thən \

Definition of agnathan

plural agnathans
:jawless fish
  • Two jawless fishes (agnathans) are recognized in these fossils … based on differences in the shape and histology of their tubercles …
  • —Moya Meredith Smith,  Science,  18 Jan. 1991

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Origin and Etymology of agnathan

agnatha +1-an

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