The Collaborative International Dictionary of English v.0.48:

Preventive \Pre*vent"ive\, a. [Cf. F. pr['e]ventif.]
   1. Going before; preceding. [Obs.]
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            Any previous counsel or preventive understanding.
                                                  --Cudworth.
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   2. Tending to defeat or hinder; obviating; preventing the
      access of; as, a medicine preventive of disease.
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            Physic is either curative or preventive. --Sir T.
                                                  Browne.
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   Preventive service, the duty performed by the armed police
      in guarding the coast against smuggling. [Eng]
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