The Fila Brasileiro (Portuguese pronunciation: ), or Brazilian Mastiff, is a large working breed of dog developed in Brazil. It is known for its superb tracking ability, aggressiveness and an unforgiving, impetuous temperament. Rather than attacking its prey, the Fila traps it and waits for the hunter to arrive. Owing to these qualities, the Fila Brasileiro is used as a guard dog, as a cattle dog for livestock and as a hunting dog for tracking and controlling large game. The verb 'Filar' in Portuguese literally means 'hold, arrest, grab'. So 'Cão de Fila' (Fila dog) or 'Cão de filar' suggests that it is a 'catch dog', a dog that 'bites and does not loosen its grip'. A similar name is also found in two Portuguese dog breeds: the Cão de Fila de São Miguel and the extinct Cão de Fila da Terceira.