The term 'Large American Cat' can be summarized by two crossword solutions: PUMA (4 letters) and OCELOT (6 letters). The PUMA, also known as the Cougar or Mountain Lion, is a large cat native to the Americas. It is the second-heaviest cat in the New World after the Jaguar. The OCELOT is a small wild cat found in Central and South America. It is characterized by its spotted coat and is considered an endangered species due to habitat loss.