Source : Webster's Revised Unabridged Dictionary (1913)

Spiteful \Spite"ful\, a.
   Filled with, or showing, spite; having a desire to vex,
   annoy, or injure; malignant; malicious; as, a spiteful person
   or act. --Shak. -- {Spite"ful*ly}, adv. {Spite"ful*ness}, n.

Source : WordNet®

spitefulness
     n 1: feeling a need to see others suffer [syn: {malice}, {maliciousness},
           {spite}, {venom}]
     2: malevolence by virtue of being malicious or spiteful or
        nasty [syn: {cattiness}, {bitchiness}, {spite}, {nastiness}]