Source : Webster's Revised Unabridged Dictionary (1913)

Quietude \Qui"e*tude\, n. [L. quietudo: cf. F. qui['e]tude.]
   Rest; repose; quiet; tranquillity. --Shelley.

Source : WordNet®

quietude
     n : a state of peace and quiet [syn: {tranquillity}, {tranquility},
          {quietness}]