To boast or brag, often by exaggerating or telling tall tales; to talk big (colloquial, often derogatory).
彼は若いころの武勇伝をしょっちゅうホラを吹く。
He is always bragging about his heroic deeds from his youth.
試験で満点だったってホラを吹いていたけど、実際は違った。
He was boasting that he scored full marks on the exam, but that wasn't true.
彼の話はいつも大げさで、ホラを吹いているように聞こえる。
His stories are always exaggerated and sound like bragging.