Source : Webster's Revised Unabridged Dictionary (1913)

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.

   {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.