The Collaborative International Dictionary of English v.0.48:

Artesian \Ar*te"sian\, a. [F. art['e]sien, fr. Artois in France,
   where many such wells have been made since the middle of the
   last century.]
   Of or pertaining to Artois (anciently called Artesium), in
   France.
   [1913 Webster]

   Artesian wells, wells made by boring into the earth till
      the instrument reaches water, which, from internal
      pressure, flows spontaneously like a fountain. They are
      usually of small diameter and often of great depth.
      [1913 Webster]

WordNet (r) 3.0 (2006):

artesian
    adj 1: (of water) rising to the surface under internal
           hydrostatic pressure; "an artesian well"; "artesian
           pressure" [ant: subartesian]

U.S. Gazetteer Places (2000):

Artesian, SD -- U.S. town in South Dakota
   Population (2000):    157
   Housing Units (2000): 99
   Land area (2000):     0.549521 sq. miles (1.423252 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.549521 sq. miles (1.423252 sq. km)
   FIPS code:            02380
   Located within:       South Dakota (SD), FIPS 46
   Location:             44.007512 N, 97.923379 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Artesian, SD
    Artesian