[1] : The Collaborative International Dictionary of English v.0.48

keystone \key"stone`\, n. arch.
   the central or topmost stone of an arch. this in some styles
   is made different in size from the other voussoirs, or
   projects, or is decorated with carving. see illust. of
   arch.
   1913 webster
see also:
arch 

[2] : WordNet (r) 2.0

keystone
     n 1: a central cohesive source of support and stability; "faith
          is his anchor"; "the keystone of campaign reform was the
          ban on soft money"; "he is the linchpin of this firm"
          syn: anchor, mainstay, backbone, linchpin, lynchpin
     2: the central building block at the top of an arch or vault
        syn: key, headstone
see also:
anchor mainstay backbone linchpin lynchpin key 
headstone 

[3] : Moby Thesaurus II by Grady Ward, 1.0

68 moby thesaurus words for "keystone":
   apse, arcade, arcature, arch, arched roof, archway, basis,
   bench mark, camber, cardinal point, ceilinged roof, chief thing,
   climax, concameration, concha, core, cornerstone, cove, crisis,
   critical point, crux, cupola, dome, essence, essential,
   essential matter, first stone, footstone, foundation,
   foundation stone, fundamental, geodesic dome, gist, gravamen,
   great point, headstone, heart, high point, igloo, important thing,
   issue, kernel, landmark, main point, main thing, material point,
   meat, milestone, necessity, nub, ogive, pith, pivot, principle,
   quoin, real issue, salient point, sine qua non, skewback, span,
   substance, substantive point, the bottom line, the point,
   turning point, vault, vaulting, voussoir

[4] : U.S. Gazetteer (1990)

keystone, al
  zip codes: 35007
keystone, co
  zip codes: 80435
keystone, ia city, fips 41115
  location: 41.99976 n, 92.19858 w
  population 1990: 568 252 housing units
  area: 1.0 sq km land, 0.0 sq km water
  zip codes: 52249
keystone, in
  zip codes: 46759
keystone, ne
  zip codes: 69144
keystone, sd town, fips 33820
  location: 43.89435 n, 103.42887 w
  population 1990: 232 137 housing units
  area: 7.4 sq km land, 0.0 sq km water
  zip codes: 57751
keystone, wv city, fips 43516
  location: 37.41501 n, 81.44626 w
  population 1990: 627 302 housing units
  area: 0.8 sq km land, 0.0 sq km water

[5] : U.S. Gazetteer Places (2000)

keystone, co -- u.s. census designated place in colorado
   population 2000:    825
   housing units 2000: 2606
   land area 2000:     40.636910 sq. miles 105.249108 sq. km
   water area 2000:    0.006514 sq. miles 0.016872 sq. km
   total area 2000:    40.643424 sq. miles 105.265980 sq. km
   fips code:            40550
   located within:       colorado co, fips 08
   location:             39.604233 n, 105.948111 w
   zip codes 1990:     80435
   note: some zip codes may be omitted esp. for suburbs.
   headwords:
    keystone, co
    keystone

[6] : U.S. Gazetteer Places (2000)

keystone, fl -- u.s. census designated place in florida
   population 2000:    14627
   housing units 2000: 5709
   land area 2000:     36.078818 sq. miles 93.443706 sq. km
   water area 2000:    3.164101 sq. miles 8.194984 sq. km
   total area 2000:    39.242919 sq. miles 101.638690 sq. km
   fips code:            36462
   located within:       florida fl, fips 12
   location:             28.127550 n, 82.589117 w
   zip codes 1990:    
   note: some zip codes may be omitted esp. for suburbs.
   headwords:
    keystone, fl
    keystone

[7] : U.S. Gazetteer Places (2000)

keystone, ia -- u.s. city in iowa
   population 2000:    687
   housing units 2000: 281
   land area 2000:     0.370289 sq. miles 0.959043 sq. km
   water area 2000:    0.000000 sq. miles 0.000000 sq. km
   total area 2000:    0.370289 sq. miles 0.959043 sq. km
   fips code:            41115
   located within:       iowa ia, fips 19
   location:             42.000915 n, 92.198544 w
   zip codes 1990:     52249
   note: some zip codes may be omitted esp. for suburbs.
   headwords:
    keystone, ia
    keystone

[8] : U.S. Gazetteer Places (2000)

keystone, sd -- u.s. town in south dakota
   population 2000:    311
   housing units 2000: 209
   land area 2000:     2.864807 sq. miles 7.419816 sq. km
   water area 2000:    0.000000 sq. miles 0.000000 sq. km
   total area 2000:    2.864807 sq. miles 7.419816 sq. km
   fips code:            33820
   located within:       south dakota sd, fips 46
   location:             43.893744 n, 103.426080 w
   zip codes 1990:     57751
   note: some zip codes may be omitted esp. for suburbs.
   headwords:
    keystone, sd
    keystone

[9] : U.S. Gazetteer Places (2000)

keystone, wv -- u.s. city in west virginia
   population 2000:    453
   housing units 2000: 236
   land area 2000:     0.324252 sq. miles 0.839808 sq. km
   water area 2000:    0.000000 sq. miles 0.000000 sq. km
   total area 2000:    0.324252 sq. miles 0.839808 sq. km
   fips code:            43516
   located within:       west virginia wv, fips 54
   location:             37.415119 n, 81.446082 w
   zip codes 1990:    
   note: some zip codes may be omitted esp. for suburbs.
   headwords:
    keystone, wv
    keystone

Keystone >> K Words
Keystone, definition of term: Keystone
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