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notice; notification; warning
permission; consent
rejection; refusal; nonacceptance; declination; declining
excuse; plea
断りもなく席を立った。
He left his seat without any notice.
急な欠席なら断りの連絡が必要だ。
If you're suddenly absent, you need to let someone know.
前もって断りを入れておかないと失礼だ。
It's rude not to give advance notice.