tabbing is a fiberglass boat building term. It is a method off adding a structural piece of material onto the surface of another piece using fiberglass cloth and resin. I am including the description of tabbing and a video link
Featured snippet from the web
boats are built with plywood bulkheads laminated to the hull for strength. Typical construction (called "tabbing") involves bonding bulkheads to the hull with strips of fiberglass
cloth wetted with polyester resin. Done correctly, these tabs
give an initially strong connection that seems permanent."
here is a video link showing this done with some pieces of plywood being joined with fillets and cloth using resin