I will admit that I used the term Priory in an all inclusive mode. But, in all my research, the Prieure was the "slang" used to express the order.
PRIORY OF SION: THE FACTS, THE THEORIES, THE MYSTERY
Introduction
It has been seven years since I wrote my first article on the Priory of Sion/Rennes-les-Chateau mystery. At the time, I was heavily under the influence of the books Holy Blood, Holy Grail and Lionel Fanthorpe's work. Since then, there have been a number of books released, some better, some worse, than these original influences. I have revised some of my theories, challenged some of my own assumptions, learned some new things, and encountered a great deal of contrary data. Now, I am no longer sure that the hypothesis presented at the end of Holy Blood, Holy Grail is the best for explaining the data, nor am I sure that a Priory of Sion with the characteristics ascribed to it (an 800-year uninterrupted history, 9000 members internationally) really exists. I also am not sure that what is presented as "orthodox" with regard to the Sauniere saga can really be trusted. Still, although I have encountered the work of the debunkers, I am sure of two and only two things:
1. the Sauniere saga cannot be explained away simply by a mass-trafficking pyramid scheme and a bad taste in décor.
2. Something called the Order de Sion existed in the Middle Ages up until, at the latest, the 17th century; something called the Prieure du Sion existed from at least 1956 to 1984; whether these two things have any actual relationship to each other, I am still trying to figure out.