In sailing, a stanchion is a vertical metal post or pillar fixed around the perimeter of a sailboat's deck. They serve as critical safety components, supporting horizontal lifelines (wires or ropes) that form a safety railing to prevent crew from falling overboard. Stanchions are usually made of stainless steel.

Key Details About Stanchions:
Function: Their primary purpose is to hold lifelines, creating a protective barrier around the deck.

Structure: They are tall and slender vertical supports.

Placement: Positioned along the outer edges of the deck, often mounted on the cap-rail or deck edge.

Other Uses: In some applications, they can act as vertical structural supports for decks or roof structures, similar to a pillar.

They differ from bollards, which are short and thick and meant to withstand higher impact.