to make moot

Moot \Moot\, n. [AS. m[=o]t, gem[=o]t, a meeting; -- usually in
   comp.] [Written also {mote}.]
   1. A meeting for discussion and deliberation; esp., a meeting
      of the people of a village or district, in Anglo-Saxon
      times, for the discussion and settlement of matters of
      common interest; -- usually in composition; as, folk-moot.
      --J. R. Green.
      [1913 Webster]

   2. [From {Moot}, v.] A discussion or debate; especially, a
      discussion of fictitious causes by way of practice.
      [1913 Webster]

            The pleading used in courts and chancery called
            moots.                                --Sir T.
                                                  Elyot.
      [1913 Webster]

   {Moot case}, a case or question to be mooted; a disputable
      case; an unsettled question. --Dryden.

   {Moot court}, a mock court, such as is held by students of
      law for practicing the conduct of law cases.

   {Moot point}, a point or question to be debated; a doubtful
      question.

   {to make moot} v. t. to render moot[2]; to moot[3].
      [1913 Webster +PJC]