Find the word definition

Wikipedia
Cliftonoceras

Cliftonoceras is a barrandeoceroid type tarphycerid from the Uranoceratidae characterized by a smooth gyroconic shell with a rounded dorsum and flattened venter, and by a subvental siphuncle composed of thin connecting rings and necks that are straight ventrally, recumbent dorsally.

Cliftonoceras has been found in Middle Silurian age sediments in Tennessee and Indiana. The type species is C. quadratum.