Source : Webster's Revised Unabridged Dictionary (1913)

Regulative \Reg"u*la*tive\ (r?g"?*l?*t?v), a.
   1. Tending to regulate; regulating. --Whewell.

   2. (Metaph.) Necessarily assumed by the mind as fundamental
      to all other knowledge; furnishing fundamental principles;
      as, the regulative principles, or principles a priori; the
      regulative faculty. --Sir W. Hamilton.

   Note: These terms are borrowed from Kant, and suggest the
         thought, allowed by Kant, that possibly these
         principles are only true for the human mind, the
         operations and belief of which they regulate.

Source : WordNet®

regulative
     adj : restricting according to rules or principles; "a regulatory
           gene" [syn: {regulatory}]