wing-shell
noun1
Any of various species of marine bivalve shells formerly belonging to the genus Avicula (no longer accepted), now a synonym of Pteria, with species assigned to several genera, in which the hinge border projects like a wing.
2
Any marine gastropod shell formerly in the genus Strombus, with species now assigned to several genera, principally in the family Strombidae.
3
Archaic Any pteropod shell.