The Collaborative International Dictionary of English v.0.48:

Introduction \In`tro*duc"tion\, n. [L. introductio: cf. F.
   introduction. See Introduce.]
   [1913 Webster]
   1. The act of introducing, or bringing to notice.
      [1913 Webster]

   2. The act of formally making persons known to each other; a
      presentation or making known of one person to another by
      name; as, the introduction of one stranger to another.
      [1913 Webster]

   3. That part of a book or discourse which introduces or leads
      the way to the main subject, or part; preliminary; matter;
      preface; proem; exordium.
      [1913 Webster]

   4. A formal and elaborate preliminary treatise; specifically,
      a treatise introductory to other treatises, or to a course
      of study; a guide; as, an introduction to English
      literature.
      [1913 Webster]

WordNet (r) 3.0 (2006):

introduction
    n 1: the act of beginning something new; "they looked forward to
         the debut of their new product line" [syn: introduction,
         debut, first appearance, launching, unveiling,
         entry]
    2: the first section of a communication
    3: formally making a person known to another or to the public
       [syn: presentation, introduction, intro]
    4: a basic or elementary instructional text
    5: a new proposal; "they resisted the introduction of
       impractical alternatives"
    6: the act of putting one thing into another [syn: insertion,
       introduction, intromission]
    7: the act of starting something for the first time; introducing
       something new; "she looked forward to her initiation as an
       adult"; "the foundation of a new scientific society" [syn:
       initiation, founding, foundation, institution,
       origination, creation, innovation, introduction,
       instauration]

Moby Thesaurus II by Grady Ward, 1.0:

211 Moby Thesaurus words for "introduction":
   Vorspiel, abecedarium, abecedary, access, acknowledgments,
   acquaintance, acquaintedness, act, admission, afterpiece,
   and arithmetic, aside, avant-propos, back, back matter,
   bastard title, bibliography, bit, breakthrough, catch line,
   catchword, chaser, close acquaintance, cloture, coinage, colophon,
   coming out, committee consideration, concert overture, contents,
   contents page, copyright page, curtain, curtain call,
   curtain raiser, debate, debut, dedication, deliberation, descant,
   discovery, divertimento, divertissement, division,
   dramatic overture, elementary education, elements, embarkation,
   embarkment, embedment, endleaf, endpaper, endsheet, entrance,
   entree, entry, epilogue, episode, errata, exode, exodus, exordium,
   expository scene, filibuster, filibustering, filing, finale,
   first appearance, first reading, first steps, floating, flotation,
   flyleaf, folio, fore edge, foreword, front matter, frontispiece,
   graft, grafting, half-title page, head, hoke act, hornbook,
   impaction, impactment, implantation, import, importation,
   importing, imprint, inaugural address, inauguration, income,
   incoming, index, induction, infiltration, infix, infixion,
   infusion, ingoing, ingress, ingression, initiation, injection,
   innovation, inoculation, input, inscription, insert, insertion,
   insinuation, installation, installment, intake, intercalation,
   interjection, interlineation, interlocution, interlude, intermezzo,
   intermission, interpenetration, interpolation, introgression,
   intromission, intrusion, invention, knockdown, launching, leaf,
   leakage, leap, logrolling, maiden speech, makeup, neologism,
   new phase, novelty, number, obiter dictum, opener,
   operatic overture, overture, page, parenthesis, penetration,
   percolation, perfusion, postulate, preamble, preface, prefix,
   prefixture, preliminaries, preliminary, prelude, premise,
   presentation, presupposition, primer, proem, prolegomena,
   prolegomenon, prolepsis, prologue, propaedeutic, protasis, reading,
   reception, recto, remark, reverso, roll call, routine, rudiments,
   running title, scene, second reading, seepage, shtick, side remark,
   signature, sketch, skit, song and dance, stand-up comedy act,
   steamroller methods, striptease, subtitle, table of contents,
   tabling, tail, talkathon, tessellation, text, third reading, title,
   title page, tossing-in, trim size, turn, type page, unveiling,
   vamp, verse, verso, voluntary, vote, writing



The Devil's Dictionary (1881-1906):

INTRODUCTION, n.  A social ceremony invented by the devil for the
gratification of his servants and the plaguing of his enemies.  The
introduction attains its most malevolent development in this century,
being, indeed, closely related to our political system.  Every
American being the equal of every other American, it follows that
everybody has the right to know everybody else, which implies the
right to introduce without request or permission.  The Declaration of
Independence should have read thus:

        "We hold these truths to be self-evident:  that all men are
    created equal; that they are endowed by their Creator with certain
    inalienable rights; that among these are life, and the right to
    make that of another miserable by thrusting upon him an
    incalculable quantity of acquaintances; liberty, particularly the
    liberty to introduce persons to one another without first
    ascertaining if they are not already acquainted as enemies; and
    the pursuit of another's happiness with a running pack of
    strangers."