The crossword solution for the term 'BOND TIGHTLY' is CEMENT, which is a building material composed of a mixture of calcined limestone and clay. CEMENT is used to bind together bricks, stones, and other masonry units, as well as to fill gaps between them. It is also used in the construction of roads, bridges, and other structures. CEMENT is an important component of concrete, which is a composite material made up of CEMENT, water, sand, and gravel.