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不定 — pronunciations, definitions, and tags
HanziPinyinEnglishTags
不定búdìngindefiniteHSK 7, unknown, 12 strokes, rank #24153, Very Hard
不定búdìngindeterminateHSK 7, unknown, 12 strokes, rank #24153, Very Hard
不定búdìng(botany) adventitiousHSK 7, unknown, 12 strokes, rank #24153, Very Hard
búdìng(bu2ding4)bu ding T4
  1. 1indefinite
  2. 2indeterminate
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March 24, 2026

不定búdìng(bu2ding4)

不定 (bù dìng) refers to something that is indefinite or indeterminate, which means it lacks a fixed or certain form. This term is often used in contexts such as botany to describe adventitious roots, which appear in unusual places rather than from the main root system.

Strokes12Frequency#24153DifficultyVery Hard
Cultural note

In Chinese philosophy, the idea of uncertainty and change is prevalent, reflecting the notion of 不定 in life and nature. This connects to broader themes in Chinese thought, such as the ever-changing dynamics of the universe as described in Daoist beliefs.

Memory tip

Think of 不 (bù) as a 'no' sign, meaning 'not,' and 定 (dìng) as a 'fixed' position. Together, 不定 can be imagined as a whimsical character that refuses to be pinned down or fixed in one place, much like the unpredictable nature of adventitious roots.

Meanings of 不定

búdìng(bu2ding4)
1indefinite
2indeterminate
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About 不定

不定Simplified
12Strokes
—Radical
副形词xíngróngcíadj-adverb (adj.-adv.)Part of Speech
#—Frequency Rank
HSK 3.0L7AdvancedTOCFLL5CEFRC2

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Podcast: 不定

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AI study notes for 不定

Quick Contrast

不确定 (bù què dìng) — use 不定 when referring to something indefinite in a broader sense, while 不确定 is more specifically about uncertainty.

Usage Notes

Be cautious with the pronunciation of 不定, as incorrect tones may lead to misunderstandings. This term is more commonly used in formal contexts, especially in academic or technical discussions. A common collocation is 不定因素 (bù dìng yīn sù), meaning 'indeterminate factors.'

HSK Study Tips

不定 is not part of the HSK vocabulary list, but it relates to concepts such as 不 (bù) and 定 (dìng), which are foundational for learners. Students should focus on recognizing how negative prefixes and adjectives interact and build vocabulary around uncertainty.

Common Mistakes

Learners often confuse 不定 with similar terms like 不确定 (bù què dìng), which means 'uncertain.' For example, saying '我不定知道' (I don't know) should be corrected to '我不确定知道' to convey uncertainty properly.

AI-enhanced 2026-03-24

Pronunciation of 不定

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Component characters

不bù(negative prefix)
HSK 14 strokes一
View full entry
定dìngto set
HSK 48 strokes宀
View full entry

How to say indefinite in Chinese

“indefinite” in Chinese is不定búdìng

不定 (bù dìng) refers to something that is indefinite or indeterminate, which means it lacks a fixed or certain form. This term is often used in contexts such as botany to describe adventitious roots, which appear in unusual places rather than from the main root system.

When to use 不定

Be cautious with the pronunciation of 不定, as incorrect tones may lead to misunderstandings. This term is more commonly used in formal contexts, especially in academic or technical discussions. A common collocation is 不定因素 (bù dìng yīn sù), meaning 'indeterminate factors.'

不定 or something close to it

不确定 (bù què dìng) — use 不定 when referring to something indefinite in a broader sense, while 不确定 is more specifically about uncertainty.

What learners get wrong

Learners often confuse 不定 with similar terms like 不确定 (bù què dìng), which means 'uncertain.' For example, saying '我不定知道' (I don't know) should be corrected to '我不确定知道' to convey uncertainty properly.

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不
定

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Frequently asked questions about 不定

In botany, 不定 refers to adventitious roots that grow from unusual locations, rather than from the main root system.

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