ろくに～ない

• Reading: ろくに
• Romaji: rokuni
• Formation: ろくに + Verb ない-form / ろくに + Noun + も + Verb ない-form
• Kanji breakdown: 碌: 石 (stone) + 录 (record) — originally meaning smooth or even, extended to mean satisfactory

Meaning

A structure indicating that someone does not or cannot do something properly, adequately, or sufficiently. It always pairs with a negative predicate and carries a critical or regretful tone.

ろくに is an adverb derived from 碌 (ろく), meaning satisfactory or decent. When paired with a negative predicate, it means 'not properly' or 'hardly at all.' The emphasis is on inadequacy — the action exists but falls far below an acceptable standard, or barely happens. It often conveys criticism, self-reproach, or lamentation. Unlike あまり～ない (not very much), which is neutral, ろくに～ない implies that the lack is problematic or falls below expectations. This pattern is primarily used in spoken Japanese and informal writing. Learners sometimes forget that ろくに requires a negative ending, producing ungrammatical affirmative sentences.

Examples

1. 忙しくてろくに食事もとれなかった。 I was so busy I could hardly eat a proper meal.
2. 彼はろくに説明もせずに帰ってしまった。 He left without even giving a proper explanation.
3. 昨日はろくに眠れなかった。 I could hardly sleep last night.

Usage Guide

Context: spoken, informal writing

Tone: critical

Do Say

• 最近ろくに運動もしていない。
• あの人はろくに挨拶もできない。
• 試験前なのにろくに勉強していなかった。

Don't Say

• ろくに食事をとった。(Using ろくに with an affirmative predicate — ろくに always requires a negative ending) → ろくに食事もとれなかった。
• あまりに説明もせずに帰った。(Using あまりに instead of ろくに — あまりに means excessively, which reverses the intended meaning of insufficiency) → ろくに説明もせずに帰った。

Origin & History

From 碌 (ろく), meaning satisfactory or proper, combined with に (adverbial particle). The character 碌 originally meant smooth or regular. ろくに～ない literally means 'not in a satisfactory manner.'

Cultural Context

Generation: All ages

Social background: Universal