expression, godan verb (-ru)
take down a peg; cut down to size; deflate someone's arrogance
Idiomatic expression meaning to humble someone who is overly proud or arrogant, often by a sharp remark or action.
彼の自慢話を聞いて、一言で鼻っ柱をへし折ってやった。
After listening to his boasting, I cut him down to size with a single remark.
It's not good to say things that dampen a newcomer's confidence.