The projecting solid angle formed by the meeting of two vaults, growing more obtuse as it approaches the summit.

The surface formed by two such vaults.

A frame of woodwork across a beach to accumulate and retain shingle.

Groin - A long, narrow, man-made jetty, usually extending roughly perpendicular to the shoreline to protect the bank or shore from erosion.

The line between the lower part of the abdomen and the thigh, or the region of this line; the inguen.

Part of the body located along the fold or crease formed where the thighs connect to the lower abdomen.

the crease at the junction of the inner part of the thigh with the trunk together with the adjacent region and often including the external genitals

the region where the abdomen and thighs join.