一不小心

• ピンイン: yī bù xiǎo xīn
• 漢字の分解: 一 = single horizontal stroke (one/once); 不 = negation particle (pictographic — a bird flying upward and not returning, suggesting refusal or absence); 小 = three small dots or strokes (small/little); 心 = pictographic heart shape (heart/mind)

意味

うっかりして／少しの不注意で

A colloquial adverbial phrase. It introduces either a past accident (一不小心就摔倒了) or a hypothetical risk (一不小心就会出错). The structure implies the ease with which something can go wrong, often with a slightly rueful or cautionary tone.

例文

1. 他在山间小路上快步行走，一不小心踩到湿滑的落叶，整个人向前扑倒，擦破了手掌。
2. 这道题目的逻辑陷阱极为隐蔽，一不小心就会选错答案，考生必须逐字审题才能避免失分。
3. 那幅古画的颜料十分脆弱，修复师在操作时必须屏气凝神，因为一不小心就可能造成不可逆的损坏。

使い方ガイド

場面: daily life, cautionary advice, narrative, risk

トーン: cautionary

正しい言い方

• 操作高压电气设备时必须严格遵守安全规程，一不小心就可能引发电弧闪烁，造成严重烧伤甚至危及生命。(When operating high-voltage electrical equipment, safety regulations must be strictly followed; a single momentary lapse in attention could trigger an arc flash, causing serious burns or even life-threatening injuries.)
• 他在演讲途中停顿时间过长，一不小心被听众误认为是忘词，尽管他只是在整理下一段论点的思路。(He paused too long during his speech and was accidentally mistaken by the audience for having forgotten his lines, even though he was simply organising his thoughts for the next argument.)

避ける言い方

• 一不小心地做了 — 一不小心 is an adverbial phrase and does not take 地; it directly precedes the verb or result clause without any structural particle

起源と歴史

一 (once/one instance of) + 不 (not) + 小心 (careful) — literally 'once [being] not careful', i.e. a single moment of inattention

文化的背景

時代: Modern

世代: All ages

社会的背景: Universal