What does the word aback mean?

Usage examples for aback

  1. Mr. Atkins himself seemed a trifle taken aback. – Cy Whittaker's Place by Joseph C. Lincoln
  2. General Rolleston was quite taken aback for a moment. – Foul Play by Charles Reade Dion Boucicault
  3. Quest, astonished and taken aback at such a universal revelation of the contempt in which he seemed to be held, found no reply ready- nothing at hand except another glass of whiskey and soda. – The Danger Mark by Robert W. Chambers