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Related to agnathan: Osteichthyes
Any of various fishes lacking jaws, including the hagfishes and the lampreys and many extinct groups, such as the ostracoderms.
(Animals) any jawless eel-like aquatic vertebrate of the superclass Agnatha, which includes the lampreys and hagfishes
(Zoology) of, relating to, or belonging to the superclass Agnatha. See also cyclostome
[C19: from New Latin agnatha, from a-1 + Greek gnathos jaw]
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|Noun||1.||agnathan - eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms|
aquatic vertebrate - animal living wholly or chiefly in or on water
Agnatha, superclass Agnatha - superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms
ostracoderm - extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic
heterostracan - extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian
anaspid - extinct small freshwater jawless fish usually having a heterocercal tail and an armored head; of the Silurian and Devonian
conodont - small (2 inches long) extinct eellike fish with a finned tail and a notochord and having cone-shaped teeth containing cellular bone; late Cambrian to late Triassic; possible predecessor of the cyclostomes
cyclostome - primitive aquatic vertebrate
lamper eel, lamprey, lamprey eel - primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tongue