The borzoi is a breed of domestic dog also called the Russian wolfhound and descended from dogs brought to Russia from central Asian countries. It is similar in shape to a greyhound, and is also a member of the sighthound family. The system by which Russians over the ages named their sighthounds was a series of descriptive terms, not actual names. "Borzói" is the masculine singular form of an archaic Russian adjective that means "fast." In Russia today the breed we know as the borzoi is officially known as "Russkaya Psovaya Borzaya". Borzoi are large Russian sighthounds that resemble some central Asian breeds such as the Afghan hound, Saluki, and the Kyrgyz Taigan. They can generally be described as "long-haired greyhounds", though Borzoi come in virtually any color. The long top-coat is silky and quite flat, with varying degrees of waviness or curling. The soft undercoat thickens during winter or in cold climates, but is shed in hot weather to prevent overheating. In its texture and distribution over the body, the borzoi coat is unique. There should be a frill on its neck, as well as feathering on its hindquarters and tail. Borzoi males frequently weigh more than 100 pounds (45 kg), ~120 pounds. Males stand at least 30 inches (about 80 centimeters) at the shoulder, while the height of females is around 26 inches (about 66 centimeters). Despite their size, the overall impression is of streamlining and grace, with a curvy shapeliness and compact strength. Stated life expectancy is 10 to 12 years. Median lifespan based on a UK Kennel Club survey is 9 years 1 month. 1 in 5 died of old age, at an average of 10 to 11.5 years. The longest lived dog lived to 14 years 3 months. Dogs that are physically fit and vigorous in their youth through middle age are more vigorous and healthy as elderly dogs, all other factors being equal. In the UK, cancer and cardiac problems seem to be the most frequent causes of premature death.