chink in someone's armor
US /tʃɪŋk ɪn ˈsʌmwʌnz ˈɑːmər/
UK /tʃɪŋk ɪn ˈsʌmwʌnz ˈɑːmər/

1.
弱点, 漏洞
a weakness or vulnerability in someone or something that is otherwise strong or well-protected
:
•
The prosecutor found a chink in the defendant's armor during cross-examination.
检察官在交叉询问中发现了被告的弱点。
•
Despite his confident exterior, there was a chink in his armor when it came to public speaking.
尽管他外表自信,但在公开演讲方面却有弱点。