A carnivore is an animal, or less commonly a plant, which eats only meat. Predators commonly hunt and kill their own prey. Scavengers are carnivores which eat animals they did not kill themselves. Carnivores which eat mainly or only insects are called insectivores. Carnivores which eat mainly or only fish are called piscivores.
The word "carnivore" describes just the scientific order Carnivora. Most Carnivora strictly eat meat. Some are to some degree omnivores, and a few such as the Giant Panda are vegetarian.
