The Collaborative International Dictionary of English v.0.48:

Colophon \Col"o*phon\ (k[o^]l"[-o]*f[o^]n), n. [L. colophon
   finishing stroke, Gr. kolofw`n; cf. L. culmen top, collis
   hill. Cf. Holm.]
   An inscription, monogram, or cipher, containing the place and
   date of publication, printer's name, etc., formerly placed on
   the last page of a book.
   [1913 Webster]

         The colophon, or final description, fell into disuse,
         and . . . the title page had become the principal
         direct means of identifying the book.    --De Morgan.
   [1913 Webster]

         The book was uninjured from title page to colophon.
                                                  --Sir W.
                                                  Scott.
   [1913 Webster]

WordNet (r) 3.0 (2006):

colophon
    n 1: a publisher's emblem printed in a book (usually on the
         title page)

Moby Thesaurus II by Grady Ward, 1.0:

151 Moby Thesaurus words for "colophon":
   PS, Parthian shot, acknowledgments, addendum, afterthought,
   appendix, back, back matter, bastard title, bibliography, billhead,
   book stamp, bookplate, boss, brand, broad arrow, bump, cachet,
   catch line, catchword, check, chorus, coda, codicil, concavity,
   conclusion, consequence, contents, contents page, continuance,
   continuation, convexity, copyright page, counterfoil, countermark,
   dactylogram, dactylograph, dedication, dent, dint, docket,
   double take, dying words, embossment, endleaf, endpaper, endsheet,
   envoi, epilogue, errata, excrescence, fingerprint, flyleaf, folio,
   follow-through, follow-up, footmark, footprint, footstep,
   fore edge, foreword, fossil footprint, front matter,
   government mark, government stamp, half-title page, hallmark, head,
   ichnite, ichnolite, impress, impression, imprint, indent,
   indentation, indention, index, inscription, introduction, label,
   last words, leaf, letterhead, logo, logotype, lump, makeup,
   masthead, pad, page, parting shot, paw print, pawmark, peroration,
   pimple, plate, postface, postfix, postlude, postscript, preface,
   preliminaries, price tag, print, pug, pugmark, recto, refrain,
   registered trademark, reverso, running head, running title, seal,
   second thought, sequel, sequela, sequelae, sequelant, sequent,
   sequitur, sigil, signature, signet, stamp, step, sticker, stub,
   stud, subscript, subtitle, suffix, supplement, swan song,
   table of contents, tag, tail, tally, text, thumbmark, thumbprint,
   ticket, title, title page, token, trade name, trademark,
   trademark name, trim size, type page, verso, vestige