boot-topping noun3 •Any substance used for boot-topping, especially a mixture of tallow, sulphur or lime and rosin, which was commonly used to paint the bottoms of wooden ships, as a deterrent against weeds and barnacles, and to reduce friction. •The paint of the part of the hull that is designed to be underwater. •The process of cleaning the upper part of a ship's underwater hull and daubing it with a protecting layer of antifouling substance. formsboot-toppings
