The walruses scientific name in Latin means "tooth walking sea horse". When the walrus uses its prominent tusks to pull its bulk from the ocean onto pack ice, it looks like an animal is walking on its tusks, hence the name.
Walruses have a lot of skin, actually 20% of their bodyweight is made up of their thick hide. Under that skin, their layer of blubber is about half a foot thick! Its no wonder they can withstand the harsh Arctic weather. Walruses are capable of slowing their heartbeats in order to withstand the frigid temperatures of the arctic waters. Source: Live Science