Source : Webster's Revised Unabridged Dictionary (1913)

Grandiosity \Gran"di*os"i*ty\, n. [Cf. F. grandiosit['e], It.
   grandiosit[`a].]
   The state or quality of being grandiose,

Source : WordNet®

grandiosity
     n : high flown style; excessive use of verbal ornamentation
         [syn: {magniloquence}, {grandiloquence}, {rhetoric}]