尽じん日じつ

noun, adverb

all day long

Used adverbially to mean throughout the entire day, from morning to night. Often appears in literary or somewhat formal contexts.

• じんじつ読どく書しょにふけった。

  I spent the whole day absorbed in reading.

noun, adverb

last day of the month; last day of the year; New Year's Eve

Refers specifically to the final day of a month or year. When referring to the last day of the year, it can mean New Year's Eve. This usage is somewhat old-fashioned and may be encountered in traditional or literary contexts.

• 十じゅう二に月がつの尽じん日じつは大おおみそかとも呼よばれる。

  The last day of December is also called ōmisoka.