CHINK IN ONE'S ARMOR
chink in one's armor: translation
a chink in one's armor
Fig. a special weakness that provides a means for attacking or impressing someone otherwise invulnerable. (Alludes to an opening in a suit of armor that allows a weapon to penetrate.) •
Jane's insecurity is the chink in her armor.
•
The boss seems mean, but the chink in his armor is that he is easily flattered.