The term for an animal that can live both in water and on land is "amphibian." Amphibians, such as frogs, toads, salamanders, and newts, are a diverse class of animals characterized by their dual life stages. They typically start their life in water as larvae, where they breathe through gills and develop into adults, often losing their gills and developing lungs for life on land. Amphibians are known for their permeable skin, which allows them to absorb water and gases. They play crucial roles in ecosystems as both predators and prey, but they are also sensitive to environmental changes.