noun
imprudence; misbehavior; misunderstanding
Refers to acting on a mistaken understanding of what is proper, leading to imprudent or improper conduct. Often implies a lapse in judgment or etiquette.
彼の心得違いが原因で、会議が混乱した。
His misunderstanding caused confusion in the meeting.
そんな心得違いをすると、信用を失いますよ。
If you make that kind of misjudgment, you'll lose trust.