Agnatha

plural noun

Ag·​na·​tha

ˈag-nə-thə

1

: a superclass or other division of Vertebrata comprising those without jaws compare gnathostomata

2

: a group of carnivorous air-breathing snails without jaws

Word History

Etymology

borrowed from New Latin, from a- a- entry 2 + -gnatha -gnatha

First Known Use

1865, in the meaning defined at sense 1

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