plural noun

Definition of Placodermi

: 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

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Other Words from Placodermi

placodermoid \ ¦⸗⸗¦dərˌmȯid \ adjective

History and Etymology for Placodermi

New Latin, from plac- + Greek derma skin

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Cite this Entry

“Placodermi.” Dictionary, Merriam-Webster, Accessed 22 Sep. 2020.

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