Pooch
1920s: of unknown origin.
wiktionary
Of uncertain origin. One (unsubstantiated) conjecture is that the word comes from Putzi, a common German name given to lapdogs. [1] The name Putzi is possibly formed from German Putz + -i, influenced by German putzig(“funny, cute, small”, adjective).
Probably related to pouch.
etymonline
pooch (n.)
"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.
