Coaming is any vertical surface on a ship designed to deflect or prevent entry of water. It usually refers to raised section of deck plating around an opening, such as a hatch. Coamings also provide a frame onto which to fit a hatch cover.

The protective metal sheeting or plating protecting against water entry into ventilator shafts in large ships is called a coaming as it suits this purpose.

The term was borrowed by the aviation industry to refer to a low rim around the opening for an unenclosed cockpit.

In addition, it is the vertical surface rising from a hatch, which forestalls the ingress of water and provides a sealing surface for the hatch cover.

Coaming also refers to the raised structure around the cockpit of a kayak

Kayak

A kayak is a small, relatively narrow, human-powered boat primarily designed to be manually propelled by means of a double blade paddle.The traditional kayak has a covered deck and one or more cockpits, each seating one paddler...

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