1Day of the week — refers to each of the seven days that make up a week (Sunday through Saturday). Each day is named with the suffix 〜曜日 (e.g., 月曜日 Monday, 金曜日 Friday). Essential for talking about schedules and plans.
今日は何曜日ですか？
What day of the week is it today?
会議は毎週木曜日に行われます。
The meeting is held every Thursday.
ゴミ収集の曜日を間違えてしまった。
I got the garbage collection day wrong.
予定が立て込んでいて、何曜日が空いているかすぐには答えられない。
My schedule is packed, so I can't immediately say which day of the week is free.
祝日と曜日が重なると三連休になる。
When a national holiday falls on a weekend day, it makes a three-day weekend.