plural noun

: a group of Devonian fishes forming a subclass of Placodermi or especially formerly an order of Ostracodermi or a separate class and having the forepart of the body protected by bony plates and with an imperfectly ossified internal skeleton see coccosteidae , dinichthys
adjective or noun
plural -s

Word History


New Latin, from arthr- + -dira (from Greek deirē neck); akin to Latvian grīva mouth of a river, Old Slavic griva mane, Sanskrit grīva neck, Latin vorare to devour

First Known Use

1891, in the meaning defined above

Time Traveler
The first known use of Arthrodira was in 1891

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Cite this Entry

“Arthrodira.” Dictionary, Merriam-Webster, Accessed 25 Apr. 2024.

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