Bulldog,  also known as the British Bulldog or English Bulldog, is a medium-sized dog breed. It is a muscular, hefty dog with a wrinkled face and a distinctive pushed-in nose. The Kennel Club (UK), the American Kennel Club (US), and the United Kennel Club (US) oversee breeding records. Bulldogs are popular pets; they were the fifth most popular purebreed in the US in 2017 according to the American Kennel Club.