Source : Webster's Revised Unabridged Dictionary (1913)

Astound \As*tound"\, v. t. [imp. & p. p. {Astounded}, [Obs.]
   {Astound}; p. pr. & vb. n. {Astounding}.] [See {Astound}, a.]
   1. To stun; to stupefy.

            No puissant stroke his senses once astound.
                                                  --Fairfax.

   2. To astonish; to strike with amazement; to confound with
      wonder, surprise, or fear.

            These thoughts may startle well, but not astound The
            virtuous mind.                        --Milton.

Source : WordNet®

astounded
     adj : filled with the emotional impact of overwhelming surprise or
           shock; "an amazed audience gave the magician a standing
           ovation"; "I stood enthralled, astonished by the
           vastness and majesty of the cathedral"; "astounded
           viewers wept at the pictures from the Oklahoma City
           bombing"; "stood in stunned silence"; "stunned
           scientists found not one but at least three viruses"
           [syn: {amazed}, {astonied}, {astonished}, {stunned}]