any extinct Palaeozoic fishlike jawless vertebrate of the group Ostracodermi, characterized by a heavily armoured body
Word origin
C19: via New Latin from Greek ostrakon shell + -derm
ostracoderm in American English
(ˈɑstrəkouˌdɜːrm)
noun
any of several extinct jawless fishes of the Ordovician, Silurian, and Devonian periods, having the body enclosed in an armor of bony plates
Word origin
[1890–95; ‹ NL Ostracodermi, pl. of Ostracodermus ‹ Gk ostrakódermos with a shell, equiv. to óstrako(n) shell, tile + -dermos-derm]This word is first recorded in the period 1890–95. Other words that entered Englishat around the same time include: cholesterol, historicism, honky-tonk, phoneme, takedown