Source : Webster's Revised Unabridged Dictionary (1913)

Half \Half\ (h[aum]f), a. [AS. healf, half, half; as a noun,
   half, side, part; akin to OS., OFries., & D. half, G. halb,
   Sw. half, Dan. halv, Icel. h[=a]lfr, Goth. halbs. Cf.
   {Halve}, {Behalf}.]
   1. Consisting of a moiety, or half; as, a half bushel; a half
      hour; a half dollar; a half view.

   Note: The adjective and noun are often united to form a
         compound.

   2. Consisting of some indefinite portion resembling a half;
      approximately a half, whether more or less; partial;
      imperfect; as, a half dream; half knowledge.

            Assumed from thence a half consent.   --Tennyson.

   {Half ape} (Zo["o]l.), a lemur.

   {Half back}. (Football) See under 2d {Back}.

   {Half bent}, the first notch, for the sear point to enter, in
      the tumbler of a gunlock; the halfcock notch.

   {Half binding}, a style of bookbinding in which only the back
      and corners are in leather.

   {Half boarder}, one who boards in part; specifically, a
      scholar at a boarding school who takes dinner only.

   {Half-breadth plan} (Shipbuilding), a horizontal plan of the
      half a vessel, divided lengthwise, showing the lines.

   {Half cadence} (Mus.), a cadence on the dominant.

   {Half cap}, a slight salute with the cap. [Obs.] --Shak.

   {A half cock}, the position of the cock of a gun when
      retained by the first notch.

Source : WordNet®

half binding
     n : book binding in which the spine and part of the sides are
         bound in one material and the rest in another