Boottopping \Boot"top`ping\, 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]