Source : Webster's Revised Unabridged Dictionary (1913)

Boastful \Boast"ful\, a.
   Given to, or full of, boasting; inclined to boast; vaunting;
   vainglorious; self-praising. -- {Boast"ful*ly}, adv. --
   {Boast"ful*ness}, n.

Source : WordNet®

boastful
     adj : exhibiting self-importance; "big talk" [syn: {braggart(a)},
           {bragging(a)}, {braggy}, {big}, {cock-a-hoop}, {crowing},
            {self-aggrandizing}, {self-aggrandising}]