23 (twenty-three) is the natural number following 22 and preceding 24; Year 23 (XXIII) was a common year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Pollio and Vetus (or, less frequently, year 776 Ab urbe conduit). This page is for quotes related to either the year or the number.

For some time past there has been going the rounds of the men about town the slang phrase "Twenty-three." The meaning attached to it is to "move on," "get out," "goody-bye, glad you are gone," "your move" and so on. ~ The Morning Herald (17 March 1899)
Quotes related to the number.
  • For some time past there has been going the rounds of the men about town the slang phrase "Twenty-three." The meaning attached to it is to "move on," "get out," "goody-bye, glad you are gone," "your move" and so on. To the initiated it is used with effect in a jocular manner.
    It has only a significance to local men and is not in vogue elsewhere. Such expressions often obtain a national use, as instanced by "rats!" "cheese it," etc., which were once in use throughout the length and breadth of the land.
    Such phrases originated, no one can say when. It is ventured that this expression originated with Charles Dickens in the Tale of Two Cities. Though the significance is distorted from its first use, it may be traced. The phrase "Twenty-three" is in a sentence in the close of that powerful novel. Sidney Carton, the hero of the novel, goes to the guillotine in place of Charles Darnay, the husband of the woman he loves. The time is during the French Revolution, when prisoners were guillotined by the hundred. The prisoners are beheaded according to their number. Twenty-two has gone and Sidney Carton answers to — Twenty-three. His career is ended and he passes from view.
    • "Twenty Three : Did The Slang Phrase Originate In Dickens' Tale Of Two Cities?" The Morning Herald [Kentucky] (17 March 1899), pg. 4
 
While Burroughs was thinking about this crude example of the irony of the gods that evening, a bulletin on the radio announced the crash of an airliner in Florida, USA. The pilot was another Captain Clark and the flight was Flight 23. ~ Robert Anton Wilson
The 23 enigma refers to a belief that most incidents and events are directly connected to the number 23.
 
One theory is that "23" is the number of the last victim in the then-popular play version of Charles Dickens's novel A Tale of Two Cities, titled The Only Way.
"Skidoo" probably comes from "skedaddle," a term made popular during the Civil War.
23 skidoo (sometimes 23 skiddoo) is an American slang phrase popularized during the early 20th century. It generally refers to leaving quickly, being forced to leave quickly by someone else, or taking advantage of a propitious opportunity to leave, that is, "getting [out] while the getting's good." The exact origin of the phrase is uncertain; first attested in 1906, combines two earlier expressions, "twenty-three" (1899) and "skidoo" (1901), both of which, independently and separately, referred to leaving, being kicked out, or the end of something. "23 skidoo" quickly became a popular catch-phrase after its first appearance in early 1906.
  • Today crowds gather around the Flatiron Building to admire its architecture and place in New York history, but back in the early part of the 20th century, men gathered there for a vastly different reason. As many New Yorkers know, the Flatiron sits at the intersection of Broadway and Fifth Avenue, directly across from Madison Park; the layout of the streets and the park, combined with the building’s placement, can create gusts of wind strong enough to lift women’s skirts.
    Back in an era when showing any part of one’s legs was risqué, men would gather on 23rd Street hoping to catch a glimpse of a woman’s ankle or maybe even a little more. … While it isn’t used heavily today, some say the phrase “23 skidoo” came from this phenomenon. Popular in the early part of the 20th century, getting the “23 skidoo” refers to either leaving an area quickly or being forced to leave. Apparently, the effect of the wind at this intersection was well known and crowds of men would gather in hopes of seeing some skin.
  • WHERE DID "23" — THE MEANING OF WHICH IS GET OUT FIRST ORIGINATE?; There are a Lot of People Who Lay Claim to the Latest Slang Term of the Day. THE INTERPRETATION OF IT IS "SKIDDOO," OF COURSE But its Origin is Shrouded in Mystery, and it May be that "Police Gazette" Readers Can Throw Some Light on the Subject.
    • The National Police Gazette (7 July 1906) Vol. LXXXIX, No. 1508, p. 6
  • One of the popular New York City myths is that the slang term "twenty-three skidoo" comes from the Flatiron Building at Twenty-Third Street and Broadway/Fifth Avenue. Tourist buses pass by this spot; they have to talk about something.
    The area has high winds, lifting women's skirts up. Allegedly, an Officer Kane told some naughty boys to "twenty-three skidoo" from the scene. Scram! Beat it! Go away!
    The problem here is that I've found articles about "twenty-three" in 1899. The Flatiron Building was completed in 1902. One theory is that "23" is the number of the last victim in the then-popular play version of Charles Dickens's novel A Tale of Two Cities, titled The Only Way.
    "Skidoo" probably comes from "skedaddle," a term made popular during the Civil War.
    I have several articles that credit the vaudeville actor Billy B. Van with combining the two slang terms into "twenty-three skidoo."
    No doubt, the slang phrase was popular.
    No doubt, it was used at 23rd Street.


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