ostracoderm

English Thesaurus

1. extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic (noun.animal)

hypernym	:	agnathan, jawless fish, jawless vertebrate,
definition	:	eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms (noun.animal)

member meronym	:	order ostracodermi, ostracodermi,
definition	:	extinct group of armored jawless vertebrates; taxonomy is not clear (noun.animal)