1The second day of the week, coming after Sunday and before Tuesday: Monday. Often shortened to just 月曜 in casual speech.
月曜日はいつも会議があるので少し憂鬱だ。
I always have a meeting on Mondays, so I feel a bit down.
今度の月曜日、時間があったら映画に行きませんか。
Do you want to go to a movie next Monday if you have time?
月曜日の朝は道が混雑することが多い。
The roads are often crowded on Monday mornings.