: a superorder of Choanichthyes comprising the lobe-finned fishes that have existed since the Devonian but are now largely extinct, that have paired fins somewhat resembling limbs with a scaly axis fringed on one or both sides by dermal rays, and that are generalized fishes in some respects resembling elasmobranchs and in others foreshadowing terrestrial vertebrates which may have evolved from unknown early members of the group compare latimeria
2
in some classifications: a division of fishes coextensive with Choanichthyes or comprising Choanichthyes together with Cladistia compare actinistia , rhipidistia
Word History
Etymology
New Latin, from cross- + -pterygii
The Ultimate Dictionary Awaits
Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.
Expanded definitions
Detailed etymologies
Advanced search tools
All ad-free
Discover what makes Merriam-Webster Unabridged the essential choice
for true word lovers.
Copy Citation
Share