Source : Webster's Revised Unabridged Dictionary (1913)

Prairial \Prai`ri`al"\, n. [F., fr. prairie meadow.]
   The ninth month of the French Republican calendar, which
   dated from September 22, 1792. It began May, 20, and ended
   June 18. See {Vendemiaire}.

Source : WordNet®

Prairial
     n : ninth month of the Revolutionary calendar (May and June);
         the month of meadows