The Collaborative International Dictionary of English v.0.48:

Province \Prov"ince\, n. [F., fr. L. provincia; prob. fr. pro
   before, for + the root of vincere to conquer. See Victor.]
   1. (Roman Hist.) A country or region, more or less remote
      from the city of Rome, brought under the Roman government;
      a conquered country beyond the limits of Italy. --Wyclif
      (Acts xiii. 34). Milton.
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   2. A country or region dependent on a distant authority; a
      portion of an empire or state, esp. one remote from the
      capital. "Kingdoms and provinces." --Shak.
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   3. A region of country; a tract; a district.
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            Over many a tract
            of heaven they marched, and many a province wide.
                                                  --Milton.
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            Other provinces of the intellectual world. --I.
                                                  Watts.
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   4. A region under the supervision or direction of any special
      person; the district or division of a country, especially
      an ecclesiastical division, over which one has
      jurisdiction; as, the province of Canterbury, or that in
      which the archbishop of Canterbury exercises
      ecclesiastical authority.
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   5. The proper or appropriate business or duty of a person or
      body; office; charge; jurisdiction; sphere.
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            The woman'sprovince is to be careful in her economy,
            and chaste in her affection.          --Tattler.
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   6. Specif.: Any political division of the Dominion of Canada,
      having a governor, a local legislature, and representation
      in the Dominion parliament. Hence, colloquially, The
      Provinces, the Dominion of Canada.
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WordNet (r) 3.0 (2006):

province
    n 1: the territory occupied by one of the constituent
         administrative districts of a nation; "his state is in the
         deep south" [syn: state, province]
    2: the proper sphere or extent of your activities; "it was his
       province to take care of himself" [syn: province,
       responsibility]

Moby Thesaurus II by Grady Ward, 1.0:

202 Moby Thesaurus words for "province":
   Kreis, academic discipline, academic specialty,
   agricultural region, ally, ambit, applied science, arable land,
   archbishopric, archdiocese, archduchy, archdukedom, area, arena,
   arrondissement, art, bailiwick, beat, bishopric, black belt,
   body politic, boondocks, border, borderland, borough, buffer state,
   business, calling, canton, capacity, captive nation, champaign,
   character, charge, chieftaincy, chieftainry, circle, circuit,
   citrus belt, city, city-state, colony, commonweal, commonwealth,
   commune, concern, conference, congressional district,
   constablewick, corn belt, cotton belt, country, countryside,
   county, demesne, departement, department, department of knowledge,
   diocese, discipline, district, division, domain, dominion, duchy,
   dukedom, dust bowl, duty, earldom, electoral district, electorate,
   empery, empire, exurbia, farm belt, farm country, farmland, field,
   field of inquiry, field of study, free city, fruit belt, function,
   government, grand duchy, grass roots, grassland, grazing region,
   hamlet, headache, hemisphere, highlands, hundred, job,
   judicial circuit, jurisdiction, kingdom, land, lowlands,
   magistracy, mandant, mandate, mandated territory, mandatee,
   mandatory, march, meadows and pastures, metropolis,
   metropolitan area, moors, nation, nationality, natural science,
   oblast, office, okrug, ology, orb, orbit, pale, parish, part,
   place, plains, polis, polity, position, possession, power,
   prairies, precinct, principality, principate, protectorate,
   provinces, puppet government, puppet regime, pure science, pursuit,
   quarter, realm, region, republic, responsibility, riding, role,
   round, rural district, rustic region, satellite, science, section,
   see, seneschalty, settlement, sheriffalty, sheriffwick, shire,
   shrievalty, social science, soke, sovereign nation, specialty,
   sphere, stake, state, steppes, strand, study, subdiscipline,
   sultanate, superpower, synod, technicology, technics, technology,
   terrain, territory, the country, the soil, the sticks, thing,
   tobacco belt, toparchia, toparchy, town, township, tract, uplands,
   veld, village, walk, wapentake, ward, wheat belt, wide-open spaces,
   woodland, woods and fields, work, worry, yokeldom, zone