Source : Webster's Revised Unabridged Dictionary (1913)

Presumptuous \Pre*sump"tu*ous\ (?; 135), a. [L. praesumptuosus:
   cf. F. pr['e]somptueux, OF. also presumptuous. See
   {Presumption}.]
   1. Full of presumption; presuming; overconfident or
      venturesome; audacious; rash; taking liberties unduly;
      arrogant; insolent; as, a presumptuous commander;
      presumptuous conduct.

            A class of presumptuous men, whom age has not made
            cautious, nor adversity wise.         --Buckminster.

   2. Founded on presumption; as, a presumptuous idea. ``False,
      presumptuous hope.'' --Milton.

   3. Done with hold design, rash confidence, or in violation of
      known duty; willful. ``Keep back the servant also from
      presumptuous sins.'' --Ps. xix. 13.

   Syn: Overconfident; foolhardy; rash; presuming; forward;
        arrogant; insolent.

Source : WordNet®

presumptuous
     adj : excessively forward; "an assumptive person"; "on a subject
           like this it would be too assuming for me to decide";
           "the duchess would not put up with presumptuous
           servants" [syn: {assumptive}, {assuming}]