Source : Webster's Revised Unabridged Dictionary (1913)

Congregation \Con`gre*ga"tion\, n. [L. congregatio: cf. F.
   congr['e]gation.]
   1. The act of congregating, or bringing together, or of
      collecting into one aggregate or mass.

            The means of reduction in the fire is but by the
            congregation of homogeneal parts.     --Bacon.

   2. A collection or mass of separate things.

            A foul and pestilent congregation of vapors. --Shak.

   3. An assembly of persons; a gathering; esp. an assembly of
      persons met for the worship of God, and for religious
      instruction; a body of people who habitually so meet.

            He [Bunyan] rode every year to London, and preached
            there to large and attentive congregations.
                                                  --Macaulay.

   4. (Anc. Jewish Hist.) The whole body of the Jewish people;
      -- called also {Congregation of the Lord}.

            It is a sin offering for the congregation. --Lev.
                                                  iv. 21.

   5. (R. C. Ch.)
      (a) A body of cardinals or other ecclesiastics to whom as
          intrusted some department of the church business; as,
          the Congregation of the Propaganda, which has charge
          of the missions of the Roman Catholic Church.
      (b) A company of religious persons forming a subdivision
          of a monastic order.

   6. The assemblage of Masters and Doctors at Oxford or
      Cambrige University, mainly for the granting of degrees.
      [Eng.]

   7. (Scotch Church Hist.) the name assumed by the Protestant
      party under John Knox. The leaders called themselves
      (1557) Lords of the Congregation.

Source : WordNet®

congregation
     n 1: a group of people who adhere to a common faith and
          habitually attend a given church [syn: {fold}, {faithful}]
     2: an assemblage of people or animals or things collected
        together; "a congregation of children pleaded for his
        autograph"; "a great congregation of birds flew over"
     3: the act of congregating [syn: {congregating}]