The Collaborative International Dictionary of English v.0.48:

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]
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            Philosophy would solidly be established, if men
            would more carefully distinguish those things that
            they know from those that they ignore. --Boyle.
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   2. (Law) To throw out or reject as false or ungrounded; --
      said of a bill rejected by a grand jury for lack of
      evidence. See Ignoramus.
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   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.
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            Ignoring Italy under our feet,
            And seeing things before, behind.     --Mrs.
                                                  Browning.
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