The Collaborative International Dictionary of English v.0.48:

Church \Church\ (ch[^u]rch), n. [OE. chirche, chireche, cherche,
   Scot. kirk, from AS. circe, cyrice; akin to D. kerk, Icel.
   kirkja, Sw. kyrka, Dan. kirke, G. kirche, OHG. chirihha; all
   fr. Gr. kyriako`n the Lord's house, fr. kyriako`s concerning
   a master or lord, fr. ky`rios master, lord, fr. ky^ros power,
   might; akin to Skr. [,c][=u]ra hero, Zend. [,c]ura strong,
   OIr. caur, cur, hero. Cf. Kirk.]
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   1. A building set apart for Christian worship.
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   2. A Jewish or heathen temple. [Obs.] --Acts xix. 37.
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   3. A formally organized body of Christian believers
      worshiping together. "When they had ordained them elders
      in every church." --Acts xiv. 23.
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   4. A body of Christian believers, holding the same creed,
      observing the same rites, and acknowledging the same
      ecclesiastical authority; a denomination; as, the Roman
      Catholic church; the Presbyterian church.
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   5. The collective body of Christians.
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   6. Any body of worshipers; as, the Jewish church; the church
      of Brahm.
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   7. The aggregate of religious influences in a community;
      ecclesiastical influence, authority, etc.; as, to array
      the power of the church against some moral evil.
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            Remember that both church and state are properly the
            rulers of the people, only because they are their
            benefactors.                          --Bulwer.
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   Note: Church is often used in composition to denote something
         belonging or relating to the church; as, church
         authority; church history; church member; church music,
         etc.
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   Apostolic church. See under Apostolic.

   Broad church. See Broad Church.

   Catholic church or Universal church, the whole body of
      believers in Christ throughout the world.

   Church of England, or English church, the Episcopal
      church established and endowed in England by law.

   Church living, a benefice in an established church.

   Church militant. See under Militant.

   Church owl (Zool.), the white owl. See Barn owl.

   Church rate, a tax levied on parishioners for the
      maintenance of the church and its services.

   Church session. See under Session.

   Church triumphant. See under Triumphant.

   Church work, work on, or in behalf of, a church; the work
      of a particular church for the spread of religion.

   Established church, the church maintained by the civil
      authority; a state church.
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WordNet (r) 3.0 (2006):

Church of England
    n 1: the national church of England (and all other churches in
         other countries that share its beliefs); has its see in
         Canterbury and the sovereign as its temporal head [syn:
         Anglican Church, Anglican Communion, Church of
         England]