The Collaborative International Dictionary of English v.0.48:

Consociate \Con*so"ci*ate\, v. t. [imp. & p. p. Consociated;
   p. pr. & vb. n. Consociating.]
   1. To bring into alliance, confederacy, or relationship; to
      bring together; to join; to unite. [R.]
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            Join pole to pole, consociate severed worlds.
                                                  --Mallet.
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   2. To unite in an ecclesiastical consociation. [U.S.]
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