The Collaborative International Dictionary of English v.0.48:

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.
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            The means of reduction in the fire is but by the
            congregation of homogeneal parts.     --Bacon.
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   2. A collection or mass of separate things.
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            A foul and pestilent congregation of vapors. --Shak.
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   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.
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            He [Bunyan] rode every year to London, and preached
            there to large and attentive congregations.
                                                  --Macaulay.
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   4. (Anc. Jewish Hist.) The whole body of the Jewish people;
      -- called also Congregation of the Lord.
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            It is a sin offering for the congregation. --Lev.
                                                  iv. 21.
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   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.
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   6. The assemblage of Masters and Doctors at Oxford or
      Cambrige University, mainly for the granting of degrees.
      [Eng.]
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   7. (Scotch Church Hist.) the name assumed by the Protestant
      party under John Knox. The leaders called themselves
      (1557) Lords of the Congregation.
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