Boottopping

n. 1. (Naut.) The act or process of daubing a vessel's bottom near the surface of the water with a mixture of tallow, sulphur, and resin, as a temporary protection against worms, after the slime, shells, etc., have been scraped off. [ 1913 Webster ]

2. (Naut.) Sheathing a vessel with planking over felt. [ 1913 Webster ]