Source : Webster's Revised Unabridged Dictionary (1913)

Decameron \De*cam"e*ron\, n. [It. decamerone, fr. Gr. de`ka ten
   + ? part; though quite generally supposed to be derived from
   ? day: cf. F. d['e]cam['e]ron.]
   A celebrated collection of tales, supposed to be related in
   ten days; -- written in the 14th century, by Boccaccio, an
   Italian.