last business day of the year; year-end work completion
Refers to the final working day before the New Year holiday, typically December 28, when work is wrapped up and offices close. Often used in greetings and announcements.
Today is the last business day of the year, so we'll do a big cleaning from the afternoon.
仕事納めの日には、みんなで一年の労をねぎらいます。
On the last working day of the year, everyone appreciates each other's hard work over the past year.