noun
late slip; tardy notice; report of late arrival
A written notice submitted to a school or workplace to explain a late arrival. Common in school settings.
遅刻したので、遅刻届を担任に提出した。
Because I was late, I submitted a tardy slip to my homeroom teacher.
遅刻届には理由を詳しく書く必要がある。
You need to write the reason in detail on the late slip.
Compound of 遅刻 (chikoku, 'lateness') and 届 (todoke, 'notice, report').