Source : Webster's Revised Unabridged Dictionary (1913)

Immaculate \Im*mac"u*late\, a. [L. immaculatus; pref. im- not +
   maculatus, p. p. of maculare to spot, stane, fr. macula spot.
   See {Mail} armor.]
   Without stain or blemish; spotless; undefiled; clear; pure.

         Were but my soul as pure From other guilt as that,
         Heaven did not hold One more immaculate. --Denham.

         Thou sheer, immaculate and silver fountain. --Shak.

   {Immaculate conception} (R. C. Ch.), the doctrine that the
      Virgin Mary was conceived without original sin. --
      {Im*mac"u*late*ly}, adv. -- {Im*mac"u*late*ness}, n.

Source : WordNet®

immaculate
     adj 1: completely neat and clean; "the apartment was immaculate";
            "in her immaculate white uniform"; "a spick-and-span
            kitchen"; "their spic red-visored caps" [syn: {speckless},
             {spick-and-span}, {spic-and-span}, {spic}, {spick}, {spotless}]
     2: free from stain or blemish [syn: {undefiled}]
     3: without fault or error; "faultless logic"; "speaks
        impeccable French"; "timing and technique were
        immaculate"; "an immaculate record" [syn: {faultless}, {impeccable}]