Source : Webster's Revised Unabridged Dictionary (1913)

Assumptive \As*sump"tive\, a. [L. assumptivus, fr. assumptus,
   fr. assumere.]
   Assumed, or capable of being assumed; characterized by
   assumption; making unwarranted claims. -- {As*sump"tive*ly},
   adv.

   {Assumptive arms} (Her.), originally, arms which a person had
      a right to assume, in consequence of an exploit; now,
      those assumed without sanction of the Heralds' College.
      --Percy Smith.

Source : WordNet®

assumptive
     adj 1: 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: {assuming}, {presumptuous}]
     2: accepted as real or true without proof; "an assumed increase
        in population"; "the assumed reason for his absence";
        "assumptive beliefs"; "his loyalty was taken for granted"
        [syn: {assumed}, {taken for granted(p)}]