"Prior to ratification of the Twenty-fifth Amendment in 1967, no provision existed for filling a vacancy in the office of Vice President. "
"Vacancy" means an open position. "Office" means a "position", in a fancy way. So the original example kind of translates to:
"Prior to ratification of the Twenty-fifth Amendment in 1967, no provision existed for filling an open position in the position of Vice President. "
So, it is a position within another position? Am I wrong?
So, it is poorly written?
Not necessarily. I'm not American. It may be that our AmE speakers understand the terminology of their government better than I do.
How about this:
"A vacancy in the position of elected alumnus member prior to the expiration of a term shall be filled for the remainder of the term in the same manner as elections to full terms. "
A "vacancy" means an opening, an emptiness.
This is talking about when the position of Vice President is unfilled (due to death or resignation).
I really have no difficulty reading this sentence.
Vacancy | Define Vacancy at Dictionary.com
"An open position" is definition 4. It seems to me that this sense of the word developed from shorthand. "A vacancy in the position of blank" simply became known in BrE as "a vacancy." We don't use the word that way in my experience in AmE.
Hotels/motels in America have signs which can read "vacancy" or "no vacancy." That's the common use of the word.
In the UK, you can simply say "Do you have any [job] vacancies at the moment?" Admittedly, there would be ambiguity if they went to the reception desk in a hotel with the same question because it could mean "Do you have any empty rooms?" or "Do you have any job openings?"
Yes "Are you hiring now?" is OK. Or "Do you need any help?" or even "I'm looking for a job." "Help Wanted" is the most common sign that a business would place if it was looking to hire.
Please be aware that I'm neither a native English speaker nor a teacher.