Capybara (Hyrochoerus hydrochaeris, also known as capibara, chigüiro and carpincho in Spanish, and capivara in Portuguese) is the largest living rodent in the world. It is related to agouti, chinchillas, coyphillas, and guinea pigs. Its common name, derived from Kapiÿva in the Guarani language, means "master of the grasses" while its scientific name, hydrochaeris, is Greek for "water hog".