一朝一夕

• Reading: いっちょういっせき
• Romaji: icchoisseki
• Kanji breakdown: 一 (ichi) — one | 朝 (cho) — morning | 一 (ichi) — one | 夕 (seki) — evening
• Pronunciation: /i.c.tɕo.i.s.se.ki/

Meaning

Overnight; in a brief time; in a single day. Used almost exclusively in negative contexts: not achievable quickly.

A four-character idiom (yojijukugo) meaning literally 'one morning, one evening'. Nearly always appears in the negative pattern 一朝一夕には〜できない (cannot be done overnight) to stress that something requires sustained effort over a long period. Frequently encountered in motivational, educational, and managerial discourse.

Examples

1. 信頼関係は一朝一夕には築けないと、彼は部下に繰り返し説いた。 He repeatedly told his subordinates that trust cannot be built overnight.
2. 語学の習得は一朝一夕にはいかないが、積み重ねが必ず報われる。 Mastering a language cannot be done in a single day, but consistent effort will always pay off.
3. 長年の慣習を変えることは、一朝一夕にできることではない。 Changing long-established customs is not something that can be accomplished overnight.

Usage Guide

Context: education, management, motivational speech, proverbs

Tone: cautionary

Origin & History

A four-character compound (四字熟語) originating from classical Chinese. 朝 (morning) and 夕 (evening) together represent the briefest span of time — a single day — emphasising that great things require more than momentary effort.

Cultural Context

Era: Classical

Generation: Adults

Social background: Universal