noun
Abbreviation of 日曜 or 日曜日, commonly seen in calendars, schedules, opening hours, and compact lists of weekdays.
See also: 日曜
この店は日・祝が休みです。
This shop is closed on Sundays and holidays.
suffix
nth day of the month; date suffix
Used after many numbers to indicate a calendar date, especially the 11th and above. Some dates have special native readings, so learners should not apply にち mechanically to every date.
締め切りは15日です。
The deadline is the 15th.
counter
counter for days; number of days
Counts a duration in days. In writing, 日 may stand alone after a number, and 日間 can be used when the duration needs to be especially clear.
完成まであと11日です。
There are eleven days left until completion.
noun
Abbreviation of 日本, mostly used in compounds and set expressions such as 日米, 日中, and 訪日 rather than as an ordinary standalone noun.
See also: 日本
日米関係は長い歴史を持つ。
Japan-U.S. relations have a long history.
The full word for Sunday; 日 is its compact abbreviation in schedules and calendars.
The normal standalone word for Japan; 日 is an abbreviation mainly used inside compounds such as 日米 and 訪日.
Explicitly marks a duration of days; plain 日 can also count days, but 日間 makes the duration reading clearer.
日 is the kanji for sun or day; にち is its Sino-Japanese on-yomi reading. Here it is used in abbreviated, date-suffix, and day-counting functions.