The Collaborative International Dictionary of English v.0.48:

Intercepter \In`ter*cept"er\, n.
   1. One who, or that which, intercepts. --Shak.
      [1913 Webster]

   2. (Mil.) A high-speed fighter airplane with fast-climbing
      capability, used to intercept enemy airplanes or identify
      unknown aircraft and engage them in combat if necessary;
      also, a missile which intercepts and destroys incoming
      missiles or airplanes.
      [PJC]