agnathan

noun

ag·​na·​than ˈag-nə-thən 

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

Word History

Etymology

agnatha + -an entry 1

First Known Use

1939, in the meaning defined above

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