The Collaborative International Dictionary of English v.0.48:

Yearbook \Year"book`\, n.
   1. A book published yearly; any annual report or summary of
      the statistics or facts of a year, designed to be used as
      a reference book; as, the Congregational Yearbook.
      [1913 Webster]

   2. (Eng. Law) A book containing annual reports of cases
      adjudged in the courts of England.
      [1913 Webster]
      [1913 Webster]

   Note: The Yearbooks are the oldest English reports extant,
         beginning with the reign of Edward II., and ending with
         the reign of Henry VIII. They were published annually,
         and derive their name from that fact. They consist of
         eleven parts, or volumes, are written in Law French,
         and extend over nearly two hundred years. There are,
         however, several hiatuses, or chasms, in the series.
         --Kent. --Bouvier.
         [1913 Webster]

WordNet (r) 3.0 (2006):

yearbook
    n 1: a book published annually by the graduating class of a high
         school or college usually containing photographs of faculty
         and graduating students
    2: a reference book that is published regularly once every year
       [syn: annual, yearly, yearbook]

Moby Thesaurus II by Grady Ward, 1.0:

78 Moby Thesaurus words for "yearbook":
   Domesday Book, account, account book, account rendered, accounting,
   acta, address book, adversaria, album, annual,
   appointment calendar, appointment schedule, bimonthly, biweekly,
   blankbook, blotter, brief, bulletin, calendar, cashbook, catalog,
   census report, classified catalog, commonplace book,
   court calendar, daily, daybook, desk calendar, diary, diptych,
   docket, election returns, engagement book, ephemeris, fortnightly,
   gazette, journal, ledger, log, logbook, loose-leaf notebook,
   magazine, memo book, memorandum book, memory book, minutes,
   monthly, newsmagazine, notebook, organ, pad, periodical,
   petty cashbook, pictorial, pocket notebook, pocketbook,
   police blotter, proceedings, quarterly, report, returns, review,
   scrapbook, scratch pad, serial, slick magazine, spiral notebook,
   statement, table, tablet, tally, the record, trade magazine,
   transactions, triptych, weekly, workbook, writing tablet