Unguis is a Latin term used to describe the hard, protective outer covering of animals such as mammals, birds, reptiles, and amphibians. The crossword solutions for this term are CLAW (4 letters), FANG (4 letters), HOOF (4 letters), and NAIL (4 letters). The combination of these four terms is Nailclawhoof (12 letters). These four terms refer to the various types of unguis found in different animals, such as claws, fangs, hooves, and nails.