Source : Webster's Revised Unabridged Dictionary (1913)

Fud \Fud\, n. [Of uncertain origin.]
   1. The tail of a hare, coney, etc. [Prov. Eng. & Scot.]
      --Burns.

   2. Woolen waste, for mixing with mungo and shoddy.

Source : Free On-Line Dictionary of Computing

FUD
     
         /fuhd/ An acronym invented by {Gene Amdahl}
        after he left {IBM} to found his own company: "FUD is the
        fear, uncertainty, and doubt that {IBM} sales people instill
        in the minds of potential customers who might be considering
        [Amdahl] products."  The idea, of course, was to persuade them
        to go with safe IBM gear rather than with competitors'
        equipment.  This implicit coercion was traditionally
        accomplished by promising that Good Things would happen to
        people who stuck with IBM, but Dark Shadows loomed over the
        future of competitors' equipment or software.
     
        [{Jargon File}]
     
        (1995-05-23)