NOUN (5)

1. a subdivision of a written work; usually numbered and titled;
- Example: "he read a chapter every night before falling asleep"

2. any distinct period in history or in a person's life;
- Example: "the industrial revolution opened a new chapter in British history"
- Example: "the divorce was an ugly chapter in their relationship"

3. a local branch of some fraternity or association;
- Example: "he joined the Atlanta chapter"

4. an ecclesiastical assembly of the monks in a monastery or even of the canons of a church;

5. a series of related events forming an episode;
- Example: "a chapter of disasters"

The Collaborative International Dictionary of English v.0.48:

Chapter \Chap"ter\, n. [OF. chapitre, F. chapitre, fr. L.
   capitulum, dim. of caput head, the chief person or thing, the
   principal division of a writing, chapter. See Chief, and
   cf, Chapiter.]
   1. A division of a book or treatise; as, Genesis has fifty
      chapters.
      [1913 Webster]

   2. (Eccl.)
      (a) An assembly of monks, or of the prebends and other
          clergymen connected with a cathedral, conventual, or
          collegiate church, or of a diocese, usually presided
          over by the dean.
      (b) A community of canons or canonesses.
      (c) A bishop's council.
      (d) A business meeting of any religious community.
          [1913 Webster]

   3. An organized branch of some society or fraternity as of
      the Freemasons. --Robertson.
      [1913 Webster]

   4. A meeting of certain organized societies or orders.
      [1913 Webster]

   5. A chapter house. [R.] --Burrill.
      [1913 Webster]

   6. A decretal epistle. --Ayliffe.
      [1913 Webster]

   7. A location or compartment.
      [1913 Webster]

            In his bosom! In what chapter of his bosom? --Shak.
      [1913 Webster]

   Chapter head, or Chapter heading, that which stands at
      the head of a chapter, as a title.

   Chapter house, a house or room where a chapter meets, esp.
      a cathedral chapter.

   The chapter of accidents, chance. --Marryat.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Chapter \Chap"ter\, v. t.
   1. To divide into chapters, as a book. --Fuller.
      [1913 Webster]

   2. To correct; to bring to book, i. e., to demand chapter and
      verse. [Obs.] --Dryden.
      [1913 Webster]

WordNet (r) 3.0 (2006):

chapter
    n 1: a subdivision of a written work; usually numbered and
         titled; "he read a chapter every night before falling
         asleep"
    2: any distinct period in history or in a person's life; "the
       industrial revolution opened a new chapter in British
       history"; "the divorce was an ugly chapter in their
       relationship"
    3: a local branch of some fraternity or association; "he joined
       the Atlanta chapter"
    4: an ecclesiastical assembly of the monks in a monastery or
       even of the canons of a church
    5: a series of related events forming an episode; "a chapter of
       disasters"