Source : Webster's Revised Unabridged Dictionary (1913)

Impede \Im*pede"\, v. t. [imp. & p. p. {Impeded}; p. pr. & vb.
   n. {Impeding}.] [L. impedire, lit., to entangle the feet;
   pref. im- in + pes, pedis, foot. See {Foot}, and cf.
   {Impeach}.]
   To hinder; to stop in progress; to obstruct; as, to impede
   the advance of troops.

         Whatever hinders or impedes The action of the nobler
         will.                                    --Logfellow.

Source : WordNet®

impede
     v 1: be a hindrance or obstacle to; "She is impeding the progress
          of our project" [syn: {hinder}]
     2: block passage through; "obstruct the path" [syn: {obstruct},
         {obturate}, {occlude}, {jam}, {block}, {close up}] [ant:
        {free}]