Source : Webster's Revised Unabridged Dictionary (1913)

Prefatory \Pref"a*to*ry\, a.
   Pertaining to, or of the nature of, a preface; introductory
   to a book, essay, or discourse; as, prefatory remarks.

         That prefatory addition to the Creed.    --Dryden.

Source : WordNet®

prefatory
     adj : serving as an introduction or preface [syn: {introductory},
           {prefatorial}]