ostracoderm

 
Pronunciation: /ɒˈstrakədəːm/

noun

  • an early jawless fossil fish of the Cambrian to Devonian periods, having a heavily armoured body.
    • Class Agnatha: several orders

Origin:

late 19th century: from modern Latin Ostracodermi (former taxonomic name), from Greek ostrakon 'shell' + derma 'skin'