The term 'Aquatic Animal' encompasses a wide variety of creatures, including the four solutions provided in the crossword: SEAL (4 letters), FISH (4 letters), Otter (5 letters), and Earedseal (9 letters). Seals are semi-aquatic mammals that live in the ocean and have flippers instead of feet. FISH are aquatic vertebrates that breathe through gills and have fins for swimming. Otters are semi-aquatic mammals that have webbed feet and a thick fur coat to keep them warm in the water. Earedseals are a type of SEAL that have external ears and are found in both the Atlantic and Pacific oceans.