day of the week
Refers to the seven named days of the week (Monday–Sunday). Often used in compounds like 月曜日 (Monday).
What day of the week is it today?
Please come again on the same day of the week next week.
The supermarket's business hours differ depending on the day of the week.
What day of the week is it today?
I checked the day of the week before making plans.
same day of the week