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

1 sense of heterostracan

Sense 1
heterostracan -- (extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian)
       => jawless vertebrate, jawless fish, agnathan -- (eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms)