The Collaborative International Dictionary of English v.0.48:

Territory \Ter"ri*to*ry\, n.; pl. Territories. [L.
   territorium, from terra the earth: cf. F. territoire. See
   Terrace.]
   1. A large extent or tract of land; a region; a country; a
      district.
      [1913 Webster]

            He looked, and saw wide territory spread
            Before him -- towns, and rural works between.
                                                  --Milton.
      [1913 Webster]

   2. The extent of land belonging to, or under the dominion of,
      a prince, state, or other form of government; often, a
      tract of land lying at a distance from the parent country
      or from the seat of government; as, the territory of a
      State; the territories of the East India Company.
      [1913 Webster]

   3. In the United States, a portion of the country not
      included within the limits of any State, and not yet
      admitted as a State into the Union, but organized with a
      separate legislature, under a Territorial governor and
      other officers appointed by the President and Senate of
      the United States. In Canada, a similarly organized
      portion of the country not yet formed into a Province.
      [1913 Webster]

WordNet (r) 3.0 (2006):

territory
    n 1: a region marked off for administrative or other purposes
         [syn: district, territory, territorial dominion,
         dominion]
    2: an area of knowledge or interest; "his questions covered a
       lot of territory"
    3: the geographical area under the jurisdiction of a sovereign
       state; "American troops were stationed on Japanese soil"
       [syn: territory, soil]

Moby Thesaurus II by Grady Ward, 1.0:

190 Moby Thesaurus words for "territory":
   Kreis, Lebensraum, acres, air space, airspace, alluvion, alluvium,
   ally, ambit, arable land, archbishopric, archdiocese, archduchy,
   archdukedom, area, arrondissement, back country, bailiwick, belt,
   bishopric, body politic, borough, buffer state, canton,
   captive nation, champaign, chieftaincy, chieftainry, city,
   city-state, clay, clear space, clearance, clearing, clod, colony,
   commonweal, commonwealth, commune, confines,
   congressional district, constablewick, constituency,
   continental shelf, corridor, country, county, crust, demesne,
   departement, department, desert, diocese, dirt, distant prospect,
   district, division, domain, dominion, dry land, duchy, dukedom,
   dust, earldom, earth, electoral district, electorate, empery,
   empire, empty view, environs, footing, free city, freehold, glade,
   glebe, government, grand duchy, grassland, ground, hamlet,
   heartland, hinterland, hundred, kingdom, land, landholdings,
   lithosphere, living space, magistracy, mandant, mandate,
   mandated territory, mandatee, mandatory, marginal land, marl,
   metropolis, metropolitan area, milieu, mold, nation, nationality,
   neighborhood, oblast, offshore rights, okrug, open country,
   open space, orbit, outback, parish, part, parts, patch, place,
   plain, polis, polity, possession, power, prairie, precinct,
   precincts, premises, principality, principate, protectorate,
   province, puppet government, puppet regime, purlieu, purlieus,
   quarter, real estate, real property, realm, region, regolith,
   republic, riding, salient, satellite, section, sector, seneschalty,
   settlement, sheriffalty, sheriffwick, shire, shrievalty, sod, soil,
   soke, sovereign nation, space, sphere, sphere of influence, stake,
   stamping ground, state, steppe, subaerial deposit, subsoil,
   sultanate, superpower, terra, terra firma, terrain, the country,
   three-mile limit, toparchia, toparchy, topsoil, town, township,
   tract, turf, twelve-mile limit, vantage, vicinage, vicinity,
   village, walk, wapentake, ward, wide-open spaces, wilderness,
   woodland, zone



Bouvier's Law Dictionary, Revised 6th Ed (1856):

TERRITORY. Apart of a country, separated from the rest, and subject to a
particular jurisdiction. The word is derived from terreo, and is so called
because the magistrate within his jurisdiction has the power of inspiring a
salutary fear. Dictum cat ab eo quod magistratus intra fines ejus terrendi
jus habet. Henrion de Pansy, Auth. Judiciare, 98. In speaking of the
ecclesiastical jurisdictions, Francis Duaren observes, that the
ecclesiastics are said not to have territory, nor the power of arrest or
removal, and are not unlike the Roman magistrates of whom Gellius says
vocationem habebant non prehensionem. De Sacris Eccl. Minist. lib. 1, cap.
4. In the sense it is used in the constitution of the United States, it
signifies a portion of the country subject to and belonging to the United
States, which is not within the boundary of any of them.
     2. The constitution of the United States, art. 4, s. 3, provides, that
"the congress shall have power to dispose of, and make all needful rules and
regulations respecting the territory or other property of the United States;
and nothing in this constitution shall be construed, so as to preclude the
claims of the United States or of any state."
     3. Congress possesses the power to erect territorial governments within
the territory of the United States; the power of congress over such
territory is exclusive and universal, and their legislation is subject to no
control, unless in the case of ceded territory, as far as it may be affected
by stipulations in the cessions, or by the ordinance of 1787, 3 Story's L.
U. S. 2073, under which any part of it has been settled. Story on the Const.
Sec. 1322; Rawle on the Const: 237; 1 Kent's Com. 243, 359; 1 Pet. S. C.
Rep. 511, 542, 517.
     4. The only organized territories of the United States are Oregon,
Minnesota, New Mexico and Utah. Vide Courts of the United States.