A three dog night is an extremely cold night. According to some scholars this idiom comes from Australia.
During extremely cold nights, Australian aborigines used to keep themselves warm by hugging dogs. On a slightly cold night, a man would need to hug just one dog to stay warm. This is often referred to as a one night dog. On a very cold night, he will need the body heat of at least three dogs to stay comfortable.
- As it was a three dog night, I could barely sleep.
- Don’t forget to bring your woolen clothes. The forecast says that it is going to be a three dog night.
Three Dog Night is also the name of an American rock and roll band that was very popular in the late 1960s and early 1970s.