A term used in the early 20th Century for "get lost."
Bums would sleep around 23rd St and when the cops came along they would hit them with their billy clubs and say "23 skidoo."
My grandfather was a cop down there around 1920 and told me how this term came about.
22 skidoo and 23 skidoo can be used interchangably. The phrase originated in New York City. It was the result of policemen having to disperse groups of pervey men who would hang out near the 23rd street subway stop to watch womens skirts get blown up by air coming up from the subway airshaft through the sidewalk. 23rd street is the flatiron district and was known for a high concentration of women office workers.
I think that guy over there is a cop, we betterstop insert illegal activity and 22 skidoo.
I heard it came from the cops in the early 20th Century-probably the 1920s-chasing the hookers off of 23rd Street in New York City and not catching them, thus the hookers gave the cops the "23 skidoo."