The term INCUS is a crossword solution that can be broken down into two words: ANVIL (5 letters) and BONE (4 letters). ANVIL is a tool used for metalworking, usually made of cast or wrought iron with a flat top surface. It is used to shape metal by hammering it on the ANVIL's surface. BONE is a hard, dense connective tissue found in the body of vertebrates. It is composed of collagen fibers and calcium phosphate, and provides structure and support for the body. The incus is a small BONE in the middle ear that helps transmit sound vibrations from the eardrum to the inner ear.