The term 'Duck-Billed Animal' refers to the PLATYPUS, an 8-letter word. The PLATYPUS is a semi-aquatic mammal native to eastern Australia and Tasmania. It is one of the few mammals that lay eggs instead of giving birth to live young. It has a distinctive duck-like bill, webbed feet, and a beaver-like tail. It is also known for its venomous spur on the hind feet of the male PLATYPUS. The PLATYPUS is an iconic symbol of Australia and is considered a keystone species in its ecosystem.