Source : Webster's Revised Unabridged Dictionary (1913)

Ignore \Ig*nore"\, v. t. [imp. & p. p. {Ignored}; p. pr. & vb.
   n. {Ignoring}.] [L. ignorare; pref. in- not + the root of
   gnarus knowing, noscere to become acquainted with. See
   {Know}, and cf. {Narrate}.]
   1. To be ignorant of or not acquainted with. [Archaic]

            Philosophy would solidly be established, if men
            would more carefully distinguish those things that
            they know from those that they ignore. --Boyle.

   2. (Law) To throw out or reject as false or ungrounded; --
      said of a bill rejected by a grand jury for want of
      evidence. See {Ignoramus}.

   3. Hence: To refuse to take notice of; to shut the eyes to;
      not to recognize; to disregard willfully and causelessly;
      as, to ignore certain facts; to ignore the presence of an
      objectionable person.

            Ignoring Italy under our feet, And seeing things
            before, behind.                       --Mrs.
                                                  Browning.