1Judged to be wrong, improper, or unjustifiable — going against reason or rules; a somewhat formal, written-style expression.
委員会はその提案を不可と判断した。
The committee judged the proposal to be unacceptable.
契約書の内容に不可な点があれば指摘してください。
Please point out anything improper in the contract's contents.
審査員はその演技を技術的に不可と評した。
The judges rated the performance as technically flawed.
2Not permitted, or not possible — frequently seen on signs and in rules in the form '〜不可' (e.g., 'no ~ allowed').
この駐車場は時間貸し不可、月極のみです。
This parking lot doesn't allow hourly rentals — monthly contracts only.
この物件はペット不可なので、犬は飼えない。
This property doesn't allow pets, so you can't keep a dog.
締め切りを過ぎた場合、返金は不可となります。
If the deadline has passed, a refund will not be possible.
3A failing grade in a school evaluation system — the lowest mark in a scale such as 優・良・可・不可 (excellent/good/pass/fail), indicating no credit is granted.
出席日数が足りず、この科目は不可になった。
I didn't have enough attendance days, so I failed this course.