Собачий холод⁠⁠

Я совсем забыл, что в сети можно все сейчас найти. Речь, оказывается, об австралийских аборигенах.

The commentary included in the CD set Celebrate: The Three Dog Night Story, 1965–1975 states that vocalist Danny Hutton's girlfriend, actress June Fairchild (best known as the "Ajax Lady" from the Cheech and Chongmovie Up In Smoke) suggested the name after reading a magazine article about Aboriginal Australians, in which it was explained that on cold nights they would customarily sleep while embracing a dingo, a native species of wild dog. On colder nights they would sleep with two dogs and, if the night were freezing, it was a "three dog night".

Взято отсюда.

https://en.m.wikipedia.org/wiki/Three_Dog_Night