Headwall

In physical geography and geology the headwall of a glacial cirque is its highest cliff. The term has been more broadly used to describe similar geomorphic features of non-glacial origin consisting of a concave depression with convergent slopes typically of 65 percent or greater forming the upper end of a drainage valley.

In civil engineering, a headwall is a small retaining wall placed at the outlet of a stormwater pipe or culvert.

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