1Grandiose talk or boastful, exaggerated claims; bragging beyond one's true ability (a four-character idiom).
彼はいつも大言壮語ばかりで、行動が伴わない。
He is always full of grandiose talk but his actions don't follow.
政治家の大言壮語に有権者が疑問を持った。
Voters questioned the politician's boastful rhetoric.
試合前に大言壮語するのはかえって逆効果だ。
Boasting before a match can backfire.