1.
that day, the day in question, the appointed day
The specific day being discussed or the day when an event takes place.
当日は晴れるでしょう。
It will probably be sunny on that day.
当日券を購入する。
I will purchase a same-day ticket.
当日キャンセルは料金がかかる。
Same-day cancellations incur a fee.
WORD FORMATION:
当 (this, the relevant) + 日 (day)
USAGE:
Refers to the specific day being discussed or the day of an event. Can mean "that day" (referring to a past event) or "on the day" (same-day, as opposed to in advance).
COMMON COLLOCATIONS:
- 当日券: same-day ticket
- 当日予約: same-day reservation
- 当日キャンセル: same-day cancellation
- イベント当日: the day of the event
- 当日受付: on-site registration
DAY SEQUENCE:
- 前日: the day before
- 当日: that day, the day of
- 翌日: the next day, the following day