Source : Webster's Revised Unabridged Dictionary (1913)

Determinative \De*ter"mi*na*tive\, a. [Cf. F. d['e]terminatif.]
   Having power to determine; limiting; shaping; directing;
   conclusive.

         Incidents . . . determinative of their course. --I.
                                                  Taylor.

   {Determinative tables} (Nat. Hist.), tables presenting the
      specific character of minerals, plants, etc., to assist in
      determining the species to which a specimen belongs.