first day; day one
Used for the first day of an event, period, or new situation such as work or school.
新学期の一日目は緊張する。
I get nervous on the first day of the new term.
旅行の一日目は雨だった。
The first day of the trip was rainy.
Standard kanji spelling.
Numerical variant, common in schedules and lists.
Compound of 一日 (いちにち, 'one day') and the ordinal suffix 目 (め, '-th').