The Collaborative International Dictionary of English v.0.48:

Deanery \Dean"er*y\, n.; pl. Deaneries.
   1. The office or the revenue of a dean. See the Note under
      Benefice, n., 3.
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   2. The residence of a dean. --Shak.
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   3. The territorial jurisdiction of a dean.
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            Each archdeaconry is divided into rural deaneries,
            and each deanery is divided into parishes.
                                                  --Blackstone.
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