Also see Sirius, and compare heliacal. The ancient Egyptian canicular year was computed from the heliacal rising of Sirius; the canicular cycle of 1,461 years is how long it would take a given day to pass through all seasons in an uncorrected calendar.
"dog," 1917, American English, of unknown origin. Earlier it was a dog name, attested as such by 1901 as the name of a dog owned by Dick Craine, "the Klondike pioneer" (the article in the May 12 Buffalo Courier reports: " 'Pooch' is the Alaskan name for whisky, and although the dog is not addicted to the use of this stimulant, he is a genuine Eskimo dog, and, therefore, it is appropriate"). Harvard coach "Pooch" Donovan also was much in the news during the early years of 20c.