noun
not permitted; not allowed; unacceptable
Formal or technical term for something that is not permitted or not acceptable, often used in rules, specifications, or system settings.
この操作は非許容です。
This operation is not permitted.
非許容文字が含まれています。
Unacceptable characters are included.
許容 means 'permissible' or 'allowable'; 非許容 is its direct negation.
Compound of 非 (hi, 'non-') and 許容 (kyoyō, 'permission, allowance').