noun
disapproval; non-permission; refusal to authorize
Formal noun meaning that something is not permitted or authorized. Often used in official contexts.
申請は不許可となった。
The application was not approved.
不許可の通知が届いた。
A notice of disapproval arrived.
不認可 also means 'disapproval' but is more often used for official licenses or authorizations, while 不許可 is broader.
Compound of 不 (negative prefix) and 許可 (permission).