A carnivore /ˈkɑːrnɪvɔər/ meaning 'meat eater' (Latin, caro meaning 'meat' or 'flesh' and vorare meaning 'to devour') is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging. Animals that depend solely on animal flesh for their nutrient requirements are called obligate carnivores while those that also consume non-animal food are called facultative carnivores. Omnivores also consume both animal and non-animal food, and apart from the more general definition, there is no clearly defined ratio of plant to animal material that would distinguish a facultative carnivore from an omnivore. A carnivore that sits at the top of the food chain is termed an apex predator.