Question: The *New York Times* article of this past July 29th titled, “The D.O. Is In Now:
Osteopathic Schools Turn Out Nearly a Third of All Med School Grads,” features the growing popularity of the Touro College of Osteopathic Medicine in Harlem, Manhattan among would-be doctors, and introduces the following episode:

> 
> “Gabrielle Rozenberg, in her second year at Touro, remembers the
>  **Ur-moment** that would lead her to this somewhat unconventional path in
>  medicine. Growing up on Long Island, she suffered from chronic ear
>  infections. Her doctor recommended surgery. But before committing to
>  an invasive procedure, her parents took her to a D.O. In several
>  visits, he performed some twists and turns of her neck and head, and
>  within days the infection cleared up.”
>    
>        ― *New York Times*, [“The osteopathic branch of medicine is booming”](http://www.nytimes.com/2014/08/03/education/edlife/the-osteopathic-branch-of-medicine-is-booming.html?hp&action=click&pgtype=Homepage&version=HpSumSmallMediaHigh&module=second-column-region&region=top-news&WT.nav=top-news&_r=0), 29 July 2014
> 
> 
> 

I surmise “Ur-moment” means a decisive or eureka moment in retrospect. But I don’t find this word in any English dictionaries at hand. 

Is “Ur-moment” a normal English expression? Isn’t it “Ah! (or something else)-moment”?

Answer: 
No, the prefix "ur-" is not a common construction in English, as demonstrated by the quoted writer mis-using it and their editor not noticing. As [tchrist's dictionary quotes explain](https://english.stackexchange.com/a/187750/63503), the "ur-X" is the original X. The common example is the play *Hamlet*. There seems to have been a play about a character called Hamlet floating around for about a decade before Shakespeare wrote his play. This original play is referred to the "ur-Hamlet". The prefix is also used in linguistics, philosophy and mathematical logic and set-theory.

But the writer quoted in the question talks about an "ur-moment": an original moment. The ur-moment would either be the birth of the universe or perhaps the birth or conception of the person who had the ur-moment. The moment of realising that manipulating her neck could allegedly cure ear infections is not an ur-moment but a *eureka moment* (as mentioned in the question).
The Old Testament city of Ur was a toponym, a place-name. In the story, the character Abraham, himself an originator of the monotheism practice of his tribe upon which the saga is centered, is said himself to originate from the city of Ur. 

So, the common understanding of the the usage of an "Ur-moment" would more than likely be a reference to an "origination of an originating event in one place and at time". The capitalization of the phrase adds even more credence to the theory that the source of the usage is from the Old Testament story meme.