The term 'Tusked Marine Mammal' refers to two species of animals: the WALRUS (6 letters) and the NARWHAL (7 letters). Walruses are large, flippered marine mammals that live in the Arctic Ocean and adjacent seas. They have two large tusks made of ivory, which they use for fighting, digging, and gathering food. Narwhals are also tusked marine mammals, but they are smaller than walruses and live in the cold waters of the Arctic and North Atlantic oceans. They have a single long tusk that is actually an extended tooth, which they use for defense and to break through ice.