Source : Webster's Revised Unabridged Dictionary (1913)

Cenotaph \Cen"o*taph\ (s[-e]n"[-o]*t[.a]f), n. [Gr. kenota`fion;
   keno`s empty + ta`fos burial, tomb: cf. F. c['e]notaphe.]
   An empty tomb or a monument erected in honor of a person who
   is buried elsewhere. --Dryden.

         A cenotaph in Westminster Abbey.         --Macaulay.

Source : WordNet®

cenotaph
     n : a monument built to honor soldiers who died in a war