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.
      [1913 Webster]

   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.
      [1913 Webster]

WordNet (r) 3.0 (2006):

deanery
    n 1: the official residence of a dean
    2: the position or office of a dean [syn: deanship, deanery]