plural noun

: a class of extinct fishes with an armor of large bony plates and primitive jaw structures that has been taken as equivalent to Antiarcha plus Arthrodira but is now usually extended to include also the Acanthodii, Cycliae, and minor groups compare chondrichthyes

Word History


New Latin, from plac- + Greek derma skin

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Dictionary Entries Near Placodermi

Cite this Entry

“Placodermi.” Dictionary, Merriam-Webster, Accessed 24 May. 2024.

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