The Collaborative International Dictionary of English v.0.48:

Communion \Com*mun"ion\, n. [L. communio: cf. F. communion. See
   Common.]
   1. The act of sharing; community; participation. "This
      communion of goods." --Blackstone.
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   2. Intercourse between two or more persons; esp., intimate
      association and intercourse implying sympathy and
      confidence; interchange of thoughts, purposes, etc.;
      agreement; fellowship; as, the communion of saints.
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            We are naturally induced to seek communion and
            fellowship with others.               --Hooker.
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            What communion hath light with darkness? --2 Cor.
                                                  vi. 14.
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            Bare communion with a good church can never alone
            make a good man.                      --South.
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   3. A body of Christians having one common faith and
      discipline; as, the Presbyterian communion.
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   4. The sacrament of the eucharist; the celebration of the
      Lord's supper; the act of partaking of the sacrament; as,
      to go to communion; to partake of the communion; called
      also Holy Communion.
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   Close communion. See under Close, a.

   Communion elements, the bread and wine used in the
      celebration of the Lord's supper.

   Communion service, the celebration of the Lord's supper, or
      the office or service therefor.

   Communion table, the table upon which the elements are
      placed at the celebration of the Lord's supper.

   Communion in both kinds, participation in both the bread
      and wine by all communicants.

   Communion in one kind, participation in but one element, as
      in the Roman Catholic Church, where the laity partake of
      the bread only.

   Syn: Share; participation; fellowship; converse; intercourse;
        unity; concord; agreement.
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