nivose

from WordNet (r) 3.0 (2006)

Nivose
    n 1: fourth month of the Revolutionary calendar (December and
         January); the snowy month

from The Collaborative International Dictionary of English v.0.48

Nivose \Ni`vose"\, n. [F., fr. L. nix. nivis, snow.]
   The fourth month of the French republican calendar
   [1792-1806]. It commenced December 21, and ended January 19.
   See {Vend['e]miaire}.
   [1913 Webster]