不定

• Pinyin: bù dìng
• Hanzi breakdown: 不 = 一 + 丨 (negation); 定 = 宀 + 疋 (settle under roof)

Meaning

Uncertain; indefinite. As an adverb, perhaps or maybe.

Expresses uncertainty about outcomes, quantities, or situations. Used in phrases like 说不定 for speculation and in grammar terms like 不定式 for infinitives.

Examples

1. 明天的天气还不定呢。 Tomorrow’s weather is still uncertain.
2. 这件事的结果尚且不定。 The outcome of this matter is still undecided.
3. 他说不定已经到家了。 He may already be home.

Usage Guide

Context: uncertainty, speculation, grammar

Tone: neutral

Do Say

• 计划还不定，要等领导批准。(The plan is still uncertain; we need to wait for leadership approval.)
• 说不定他会给我们一个惊喜。(Perhaps he will give us a surprise.)

Don't Say

• 我不定去 — incomplete; use 说不定 or 不一定 for expressing uncertainty about actions

Origin & History

不 (not) + 定 (fixed/certain)

Cultural Context

Generation: All ages

Social background: Universal