四六時中

• Reading: しろくじちゅう
• Romaji: shirokujichuu
• Kanji breakdown: 四 (shi) — four; 六 (roku) — six; 時 (ji) — time; 中 (chuu) — throughout
• Pronunciation: /ɕi.ɾo.kɯ.dʑi.tɕɯː/

Meaning

Around the clock; day and night; all the time; twenty-four hours a day.

An adverb and noun meaning 'all day and night' or 'constantly without break.' Derived from the old Japanese timekeeping system. More emphatic than いつも (always) and carries a literary or expressive flavour. Often used to stress that something never stops: 四六時中考えている (thinking about it around the clock).

Examples

1. 彼女のことを四六時中考えている。 I think about her around the clock.
2. この工場は四六時中稼働している。 This factory operates around the clock.
3. 四六時中スマホを見ている子どもが増えた。 More and more kids are on their phones all day and night.

Usage Guide

Context: daily life, emphasis, literature

Tone: emphatic

Origin & History

From the Edo-period timekeeping system where the day was divided into units: 四 (4) × 六 (6) = 24, representing all 24 hours. The earlier form 二六時中 (2 × 6 = 12) referenced the 12 traditional time divisions, but shifted to 四六時中 when Japan adopted the 24-hour system.

Cultural Context

Era: Edo Period

Generation: All ages

Social background: Universal