Also found in: Thesaurus, Encyclopedia, Wikipedia.
Any of various extinct primitive jawless fishes of the Ordovician through the Devonian periods, having bodies encased in an armor of bony plates.
(Palaeontology) any extinct Palaeozoic fishlike jawless vertebrate of the group Ostracodermi, characterized by a heavily armoured body
[C19: via New Latin from Greek ostrakon shell + -derm]
os•tra•co•derm(ˈɒs trə koʊˌdɜrm)
any of several extinct jawless fishes of the Ordovician to Devonian periods that had the body enclosed in an armor of bony plates.
[1890–95; < New Latin Ostracodermi, pl. of Ostracodermus < Greek ostrakódermos with a shell]
Switch to new thesaurus
|Noun||1.||ostracoderm - extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic|
agnathan, jawless fish, jawless vertebrate - eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms