Placodermi

plural noun

Plac·​o·​der·​mi

: 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

placodermoid

¦⸗⸗¦dərˌmȯid

adjective

Word History

Etymology

New Latin, from plac- + Greek derma skin

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