【动物学】无颌纲动物
【动物学】无颌纲动物的

[ noun ]
eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms
<noun.animal>

agnathan \agnathan\ n.
1. an eel-shaped vertebrate without jaws or paired
appendages; a member of the Agnatha. The group includes
the cyclostomes and some extinct forms.

Syn: jawless vertebrate, jawless fish
[WordNet 1.5]