moot point vs question

moot point

noun
  • An issue that is subject to, or open for, discussion or debate, to which no satisfactory answer is found; originally, one to be definitively determined by an assembly of the people. 

  • An issue regarded as potentially debatable, but no longer practically applicable. Although the idea may still be worth debating and exploring academically, and such discussion may be useful for addressing similar issues in the future, the idea has been rendered irrelevant for the present issue. 

question

noun
  • A doubt or challenge about the truth, accuracy, or validity of a matter. 

  • A subject or topic for consideration or investigation. 

  • A sentence, phrase or word which asks for information, reply or response; an interrogative. 

  • A proposal to a meeting as a topic for deliberation. 

verb
  • To ask a question or questions; inquire or seek to know; examine. 

  • To ask questions of; to interrogate; to ask for information. 

  • To raise doubts about; have doubts about. 

How often have the words moot point and question occurred in a corpus of books? (source: Google Ngram Viewer )