regular day off (e.g. closed every Monday)

the twentieth day of the month / twenty days / Short for 二十日鼠 (hatsuka nezumi): a house mouse

幾日も幾日も: day after day

a lucky day, auspicious day

(rare) one's birthday

Saturday

(rare) a birthday

a red sun, a bright sun, or the summer sun / a day in the traditional Japanese six-day week which is unlucky except for at noon

the last day of the year, New Year's Eve

the due date / the expiration date (of the term)