The fold where the abdomen meets the inner thigh.

• The adjacent inguinal area of the body.

The projecting edge formed where two vaults intersect.

• The curved surface created by their intersection.

A structure projecting from a beach to reduce erosion and drift.

• Typically wood, rock, or concrete, perpendicular to the shore.

To build vaults with groins.

• To construct shoreworks with groins.