Marlinspike (; sometimes marlin spike, marlinespike, or the archaic marlingspike/marling-spike) is a tool used in marine ropework. Shaped in the form of a polished metal cone tapered to a rounded or flattened point, they aid in such tasks as  rope for splicing, untying knots, drawing tight using a marlinspike hitch, and as a toggle joining ropes under tension in a belaying pin splice.

Marlinspike (; sometimes marlin spike, marlinespike, or the archaic marlingspike/marling-spike) is a tool used in marine ropework. Shaped in the form of a polished metal cone tapered to a rounded or flattened point, they aid in such tasks as  rope for splicing, untying knots, drawing tight using a marlinspike hitch, and as a toggle joining ropes under tension in a belaying pin splice.