Cyclostomata

Cy·clo·sto·ma·ta

noun pl
\ˌsī-klō-ˈstō-mət-ə, ˌsik-lō-, -ˈstäm-ət-ə\

Definition of CYCLOSTOMATA

: a class or other taxon of primitive vertebrates that have a large jawless sucking mouth, no limbs or paired fins, a wholly cartilaginous skeleton with persistent notochord, and 6 to 14 pairs of gill pouches and that include the lampreys and the hagfishes—compare chondrichthyes