\Ven`d['e]`miaire"\, n. [F., fr. L. vindemia
vintage.]
The first month of the French republican calendar, dating
from September 22, 1792.
Note: This calendar was substituted for the ordinary
      calendar, dating from the Christian era, by a decree of
      the National Convention in 1793. The 22d of September,
      1792, which had been fixed upon as the day of the
      foundation of the republic, was also the date of the
      new calendar. In this calendar, the year, which began
      at midnight of the day of the autumnal equinox, was
      divided into twelve months of thirty days, with five
      additional days for festivals, and every fourth year
      six. Each month was divided into three decades of ten
      days each, the week being abolished. The names of the
      months in their order were, Vend['e]miaire, Brumaire,
      Frimaire Nivose, Pluviose, Ventose, Germinal,
      Flor['e]al, Prairial, Messidor, Thermidor (sometimes
      called Fervidor), and Fructidor. This calendar was
      abolished December 31, 1805, and the ordinary one
      restored January 1, 1806.