object lesson
noun /ˈɒbdʒɪkt lesn/, /ˈɒbdʒekt lesn/
/ˈɑːbdʒɪkt lesn/, /ˈɑːbdʒekt lesn/
[usually singular]- a practical example of what you should or should not do in a particular situation
- Her calm handling of the emergency was an object lesson to us all.