The term for an animal that only eats plants is "herbivore." Herbivores have specialized digestive systems that allow them to effectively process plant material, which can be tough and fibrous. They consume a variety of vegetation, including leaves, fruits, seeds, and roots. Examples of herbivores include cows, deer, elephants, and rabbits. This dietary category is essential for the ecosystem, as herbivores help to control plant populations and provide a food source for predators. They play a crucial role in nutrient cycling and contribute to maintaining ecological balance.