Source : Webster's Revised Unabridged Dictionary (1913)

Black book \Black" book`\ (b[oo^]k`).
   1. One of several books of a political character, published
      at different times and for different purposes; -- so
      called either from the color of the binding, or from the
      character of the contents.

Source : WordNet®

black book
     n : a list of people who are out of favor [syn: {blacklist}, {shitlist}]