Source : Webster's Revised Unabridged Dictionary (1913)

Blur \Blur\, v. t. [imp. & p. p. {Blurred}; p. pr. & vb. n.
   {Blurring}.] [Prob. of same origin as blear. See {Blear}.]
   1. To render obscure by making the form or outline of
      confused and uncertain, as by soiling; to smear; to make
      indistinct and confused; as, to blur manuscript by
      handling it while damp; to blur the impression of a
      woodcut by an excess of ink.

            But time hath nothing blurred those lines of favor
            Which then he wore.                   --Shak.

   2. To cause imperfection of vision in; to dim; to darken.

            Her eyes are blurred with the lightning's glare.
                                                  --J. R. Drake.

   3. To sully; to stain; to blemish, as reputation.

            Sarcasms may eclipse thine own, But can not blur my
            lost renown.                          --Hudibras.

   Syn: To spot; blot; disfigure; stain; sully.

Blur \Blur\ (bl[^u]r), n.
   1. That which obscures without effacing; a stain; a blot, as
      upon paper or other substance.

            As for those who cleanse blurs with blotted fingers,
            they make it worse.                   --Fuller.

   2. A dim, confused appearance; indistinctness of vision; as,
      to see things with a blur; it was all blur.

   3. A moral stain or blot.

            Lest she . . . will with her railing set a great
            blur on mine honesty and good name.   --Udall.

Source : WordNet®

blur
     n : a hazy or indistinct representation; "it happened so fast it
         was just a blur"; "he tried to clear his head of the
         whisky fuzz" [syn: {fuzz}]
     [also: {blurring}, {blurred}]

blur
     v 1: become glassy; lose clear vision; "Her eyes glazed over from
          lack of sleep" [syn: {film over}, {glaze over}]
     2: to make less distinct or clear; "The haze blurs the hills"
        [ant: {focus}]
     3: make unclear, indistinct, or blurred; "Her remarks confused
        the debate"; "Their words obnubilate their intentions"
        [syn: {confuse}, {obscure}, {obnubilate}]
     4: make a smudge on; soil by smudging [syn: {smear}, {smudge},
        {smutch}]
     5: make dim or indistinct; "The drug blurs my vision" [syn: {blear}]
        [ant: {focus}]
     6: become vague or indistinct; "The distinction between the two
        theories blurred" [syn: {dim}, {slur}] [ant: {focus}]
     [also: {blurring}, {blurred}]