Source : Webster's Revised Unabridged Dictionary (1913)

Preventive \Pre*vent"ive\, a. [Cf. F. pr['e]ventif.]
   1. Going before; preceding. [Obs.]

            Any previous counsel or preventive understanding.
                                                  --Cudworth.

   2. Tending to defeat or hinder; obviating; preventing the
      access of; as, a medicine preventive of disease.

            Physic is either curative or preventive. --Sir T.
                                                  Browne.

   {Preventive service}, the duty performed by the armed police
      in guarding the coast against smuggling. [Eng]