Piranha are any of more than 60 species of razor-toothed carnivorous fish of South American rivers and lakes, with a somewhat exaggerated reputation for ferocity. In movies such as Piranha, the piranha has been depicted as a ravenous indiscriminate killer. These common fishes have deep bodies, and large, generally blunt heads with strong jaws bearing sharp, triangular teeth that meet in a scissor like bite.