messidor

from WordNet (r) 3.0 (2006)

Messidor
    n 1: tenth month of the Revolutionary calendar (June and July);
         the month of harvest

from The Collaborative International Dictionary of English v.0.48

Messidor \Mes`si`dor"\ (F. ?; E. ?), n. [F., fr. L. messis
   harvest.]
   The tenth month of the French republican calendar dating from
   September 22, 1792. It began June 19, and ended July 18. See
   {Vend['e]miaire}.
   [1913 Webster]