けしからぬ
Meanings
1
outrageous; scandalous; inexcusable; shameful; rude
usually written using kana alone
A strong, somewhat old-fashioned expression of moral indignation. Often used when someone's behavior is beyond acceptable limits. The form けしからん is a variant.
See also: けしからん
It is outrageous to say such a thing.
His attitude is absolutely inexcusable.