I don't believe it is on-topic.
In the question's current form the example they use is
For example, if I want a user to be able to select a time from drop down boxes with values 0-12, 00-59, and am/pm, I would name the selects Hour, Minute, and ____ ?
This is UI Design. while yes UI is something programmers may have to deal with what the front end user sees is a different thing to what a programmer practically need to know to make the frontend work.
Ask yourself, if you created javascript to change this field on the front end, will the functionality of the code be any different in the backend? in most cases probably not. at the same time, generally you could alter the code in the backend and the wording on the frontend can remain totally the same. think about a PHP Application, what you have in <label></label> will generally have zero bearing on the code that's going to be called when you POST the form
To me this feels like more something for User Experience.SE (which I don't think was around at the time) where it would be better to ask what name would be better suited for users to identify AM/PM, if any is needed (as personally, I think Users are trained enough to see an AM Dropdown and know that it can switch to PM).
Even if you were to think of it as a programming question at most it would come down to
What can I name this variable/db table field/etc which stores the AM/PM value
which is Primarily Opinion Based, even if you provide how you're storing the value (ie. for PM is it false, 0, -12, 'p', pm, etc?) naming standards aren't actuality strict globally.
So as a pure programming question, I don't see it as on-topic. as a User Experience/Interface Design Question, it might have merit though currently, it's hard to see it as anything more than as "what is the definition of _____" question
