opisthocyrt

adj. [Gr. opisthen, behind; kyrtos, curved]

1. Arched backward.

2. (MOLLUSCA: Bivalvia)

Referring to sloping in a direction posterior from the hinge axis; used to describe hinge teeth or the slope of the shell.

3. (MOLLUSCA: Gastropoda)

The growth direction of a helicocone shell; commonly referring to growth lines.