Boastingly

[f. BOASTING ppl. a. + -LY².] In a boasting or bragging manner, boastfully.

1552.  Huloet, Boastynglye, gloriose.

1561.  Norton, Calvin’s Inst., Pref. [They] doo boastyngly sett oute to sale their owne woorke.

1785.  Burke, Sp. Nab. Arcot’s Debts, Wks. IV. 272. He boastingly tells you, that he has seen, read, digested, compared every thing.

1862.  Trollope, N. Amer., I. 73. I do not say this boastingly or with pride.