Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun osteostracan

1 sense of osteostracan

Sense 1
osteostracan, cephalaspid -- (extinct jawless fish of the Devonian with armored head)
       => jawless vertebrate, jawless fish, agnathan -- (eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms)