Source : Webster's Revised Unabridged Dictionary (1913)

Grandiose \Gran"di*ose"\, a. [F. grandiose, It. grandioso. See
   {Grand}.]
   1. Impressive or elevating in effect; imposing; splendid;
      striking; -- in a good sense.

            The tone of the parts was to be perpetually kept
            down in order not to impair the grandiose effect of
            the whole.                            --M. Arnold.

            The grandiose red tulips which grow wild. --C.
                                                  Kingsley.

   2. Characterized by affectation of grandeur or splendor;
      flaunting; turgid; bombastic; -- in a bad sense; as, a
      grandiose style.

Source : WordNet®

grandiose
     adj 1: impressive because of unnecessary largeness or grandeur;
            used to show disapproval
     2: affectedly genteel [syn: {hifalutin}, {highfalutin}, {highfaluting},
         {hoity-toity}, {la-di-da}]