Source : Webster's Revised Unabridged Dictionary (1913)

Batavian \Ba*ta"vi*an\, a.
   Of or pertaining to
   (a) the Batavi, an ancient Germanic tribe; or to
   (b) ?atavia or Holland; as, a Batavian legion.

   {Batavian Republic}, the name given to Holland by the French
      after its conquest in 1795.