The term 'Big Tooth' can be broken down into three crossword solutions: MOLAR (5 letters), TUSK (4 letters), and TUSH (4 letters). A MOLAR is a large, flat tooth found in the back of the mouth that is used for grinding and crushing food. A TUSK is a long, pointed tooth found in animals such as elephants and walruses. Finally, a TUSH is a slang term for the buttocks. All three words refer to a large tooth, either in the mouth or on an animal.