What does 'any question' mean?

"Any question" places a strict limit on the number of questions allowable to exactly 1. For example, there was exactly one question as to who wore the pants. However, where the number of questions has not been determined, or is unrestricted, then the plural should be used. For Example:

How do you use “any” in a sentence?

“Any” is usually used in the negative or in questions and you can learn more about how to use “any” here. “Any Questions” is often asked at the end of a speech and is short for “do you have any questions?” or “Are there any questions?”. The word “any” is usually followed by a plural noun because “any” means that we have no objects.

What is the proper use of question versus questions?

What is the proper use of question versus questions. For example, "Please call me with any question (or questions) you may have." My boss and I are having an argument over this. Your boss is right. Related question: "Any" followed by singular or plural countable nouns? Mitch is right.