The Collaborative International Dictionary of English v.0.48:

Bishopric \Bish"op*ric\, n. [AS. bisceopr[imac]ce; bisceop
   bishop + r[imac]ce dominion. See -ric.]
   1. A diocese; the district over which the jurisdiction of a
      bishop extends.
      [1913 Webster]

   2. The office of a spiritual overseer, as of an apostle,
      bishop, or presbyter. --Acts i. 20.
      [1913 Webster]

WordNet (r) 3.0 (2006):

bishopric
    n 1: the territorial jurisdiction of a bishop [syn: diocese,
         bishopric, episcopate]

Moby Thesaurus II by Grady Ward, 1.0:

152 Moby Thesaurus words for "bishopric":
   Kreis, abbacy, aedileship, archbishopric, archdeaconry,
   archdiocese, archiepiscopacy, archiepiscopate, aristocracy,
   arrondissement, bailiwick, bishopdom, borough, canonicate, canonry,
   canton, cardinalship, chairmanship, chancellery, chancellorate,
   chancellorship, chaplaincy, chaplainship, chiefery, chiefry,
   chieftaincy, chieftainry, chieftainship, city, commune, conference,
   congressional district, constablewick, consulate, consulship,
   county, curacy, deaconry, deaconship, deanery, deanship,
   departement, dictatorship, dictature, diocese, directorship,
   district, duchy, electoral district, electorate, emirate,
   episcopacy, episcopate, government, governorship, hamlet, headship,
   hegemony, hierarchy, hundred, leadership, lordship, magistracy,
   magistrateship, magistrature, masterdom, mastership, mastery,
   mayoralty, mayorship, metropolis, metropolitan area,
   metropolitanate, metropolitanship, nobility, oblast, okrug, papacy,
   parish, pashadom, pashalic, pastorate, pastorship, patriarchate,
   patriarchy, pontificality, pontificate, popedom, popehood,
   popeship, prebend, prebendaryship, precinct, prefectship,
   prefecture, prelacy, prelateship, prelature, premiership,
   presbyterate, presbytery, presidency, presidentship, primacy,
   prime-ministership, prime-ministry, princedom, princeship,
   principality, proconsulate, proconsulship, protectorate,
   protectorship, province, provostry, provostship, rectorate,
   rectorship, regency, regentship, region, riding, ruling class, see,
   seigniory, seneschalship, seneschalsy, sheikhdom, sheriffalty,
   sheriffcy, sheriffdom, sheriffwick, shire, shrievalty, soke, stake,
   state, supervisorship, suzerainship, suzerainty, synod, territory,
   town, township, tribunate, vicariate, vicarship, village,
   vizierate, viziership, wapentake, ward