The Collaborative International Dictionary of English v.0.48:

Preface \Pref"ace\ (?; 48), n. [F. pr['e]face; cf. Sp. prefacio,
   prefacion, It. prefazio, prefazione; all fr. L. praefatio,
   fr. praefari to speak or say beforehand; prae before + fari,
   fatus, to speak. See Fate.]
   1. Something spoken as introductory to a discourse, or
      written as introductory to a book or essay; a proem; an
      introduction, or series of preliminary remarks.
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            This superficial tale
            Is but a preface of her worthy praise. --Shak.
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            Heaven's high behest no preface needs. --Milton.
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   2. (R. C. Ch.) The prelude or introduction to the canon of
      the Mass. --Addis & Arnold.
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   Proper preface (Ch. of Eng. & Prot. Epis. Ch.), a portion
      of the communion service, preceding the prayer of
      consecration, appointed for certain seasons.
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   Syn: Introduction; preliminary; preamble; proem; prelude;
        prologue.
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The Collaborative International Dictionary of English v.0.48:

Preface \Pref"ace\, v. t. [imp. & p. p. Prefaced; p. pr. & vb.
   n. Prefacing.]
   To introduce by a preface; to give a preface to; as, to
   preface a book discourse.
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The Collaborative International Dictionary of English v.0.48:

Preface \Pref"ace\, v. i.
   To make a preface. --Jer. Taylor.
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WordNet (r) 3.0 (2006):

preface
    n 1: a short introductory essay preceding the text of a book
         [syn: foreword, preface, prolusion]
    v 1: furnish with a preface or introduction; "She always
         precedes her lectures with a joke"; "He prefaced his
         lecture with a critical remark about the institution" [syn:
         precede, preface, premise, introduce]

Moby Thesaurus II by Grady Ward, 1.0:

105 Moby Thesaurus words for "preface":
   acknowledgments, anteriority, avant-propos, back, back matter,
   bastard title, begin, bibliography, bold front, brave face,
   brave front, breakthrough, catch line, catchword, colophon,
   contents, contents page, copyright page, dedication, display,
   endleaf, endpaper, endsheet, errata, exordium, facade, face, facet,
   facia, flyleaf, folio, fore, fore edge, forefront, foreground,
   forehand, foreland, forepart, forequarter, foreside, foreword,
   front, front elevation, front man, front matter, front page,
   front view, frontage, frontal, frontier, frontispiece,
   half-title page, head, heading, imprint, index, innovation,
   inscription, introduce, introduction, lap, lead, leaf, leap,
   makeup, obverse, open, overture, page, postulate, preamble,
   precede, prefix, prefixture, preliminaries, preliminary, prelude,
   premise, presupposition, priority, proem, prolegomena,
   prolegomenon, prolepsis, prologize, prologue, proscenium, protasis,
   recto, reverso, running title, signature, subtitle,
   table of contents, tail, text, title, title page, trim size,
   type page, usher, verse, verso, voluntary, window dressing