Source : Webster's Revised Unabridged Dictionary (1913)

Ignorance \Ig"no*rance\, n. [F., fr. L. ignorantia.]
   1. The condition of being ignorant; the want of knowledge in
      general, or in relation to a particular subject; the state
      of being uneducated or uninformed.

            Ignorance is the curse of God, Knowledge the wing
            wherewith we fly to heaven.           --Shak.

   2. (Theol.) A willful neglect or refusal to acquire knowledge
      which one may acquire and it is his duty to have. --Book
      of Common Prayer.

   {Invincible ignorance} (Theol.), ignorance beyond the
      individual's control and for which, therefore, he is not
      responsible before God.

Source : WordNet®

ignorance
     n : the lack of knowledge or education