Webster's Revised Unabridged Dictionary · 1913

Brag

Brag ({not transcribed}) , intransitive verb

[Old English braggen to resound, blow, boast (compare French braguer to lead a merry life, flaunt, boast, Old French brague merriment), from Icelandic braka to creak, brak noise, from the same root as English break; properly then, to make a noise, boast. {not transcribed}95.]

To talk about one's self, or things pertaining to one's self, in a manner intended to excite admiration, envy, or wonder; to talk boastfully; to boast; -- often followed by of; as, to brag of one's exploits, courage, or money, or of the great things one intends to do.
Conceit, more rich in matter than in words, Brags of his substance, not of ornament. — Shakespeare

Brag , transitive verb

To boast of. [Obsolete] — Shakespeare

Brag , noun

1.
A boast or boasting; bragging; ostentatious pretense or self glorification.
Casar... made not here his brag Of “came,” and “saw,” and “overcame.” — Shakespeare
2.
The thing which is boasted of.
Beauty is Nature's brag. — Milton
3.
A game at cards similar to bluff. — Chesterfield

Brag ({not transcribed}) , adjective

[See Brag, v. i.]

Brisk; full of spirits; boasting; pretentious; conceited. [Archaic]
A brag young fellow. — B. Jonson

Brag , adverb

Proudly; boastfully. [Obsolete] — Fuller