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凹 — pronunciations, definitions, and tags
HanziPinyinEnglishTags
凹āoa depressionHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹āoindentationHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹āoconcaveHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹āohollowHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹āoconcave, hollow; depressed; pass, valleyHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹āosunkenHSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹āo(used in names)HSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹āoindentedHSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹āofemale (connector etc)HSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāa depressionHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāindentationHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāconcaveHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāhollowHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāconcave, hollow; depressed; pass, valleyHSK 7, a, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāsunkenHSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹wā(used in names)HSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāindentedHSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
凹wāfemale (connector etc)HSK 7, unknown, 5 strokes, radical 凵, rank #11493, Very Hard
āo(ao1)ao
primary
 T1
  1. 1a depression
  2. 2indentation
Listen to the audio pronunciation 3 times to gain XP
March 24, 2026

凹āo(ao1)

The character 凹 (āo) refers to a depression or indentation, often describing surfaces that are concave or hollow. It is commonly used in contexts related to physical shapes, such as dips in terrain or objects, and can also denote a sunken or indented appearance.

Strokes5Radical凵Frequency#11493DifficultyVery Hard
Cultural note

The concept of concavity is significant in Chinese art and architecture, where curves and hollows are often used to create harmony and balance in design. The character is also found in phrases that describe natural landscapes, reflecting the appreciation of nature.

Memory tip

Imagine a bowl that is 'āo' (凹) shaped, where the inside is lower than the rim. The character has a distinct outer shape that resembles the curve of a concave surface, reminding you of a hollowed-out form.

Meanings of 凹

āo(ao1)
primary
1a depression
2indentation
Exercise 1 of 2

By ear

Play it, then pick what 凹 means.

About 凹

凹Simplified
5Strokes
凵Radical
形容词xíngróngcíadjective (adj.)Part of Speech
#11493Frequency Rank
HSK 3.0L7AdvancedTOCFLL5CEFRC2

Podcast: 凹

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Podcast: 凹

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AI study notes for 凹

Quick Contrast

凹 (āo) vs 凸 (tū) — choose 凹 when describing a concave shape, while 凸 refers to a convex shape.

Usage Notes

It's important to use 凹 in contexts where you specifically describe shapes or surfaces. Common mistakes include confusing it with 窪 (wā), which also refers to a depression but has different applications. Be careful with pronunciation, as misplacing the tone can change the meaning entirely.

HSK Study Tips

While 凹 is not part of the official HSK levels, understanding it can enhance your vocabulary related to shapes and descriptions. Focus on recognizing and using it in descriptions of objects and landscapes to improve contextual understanding.

Common Mistakes

Learners often confuse 凹 with other characters that describe similar concepts, such as 窪. For example, saying '这个地方很窪' (This place is very concave) is incorrect; instead, use '这个地方很凹'.

AI-enhanced 2026-03-24

Pronunciation of 凹

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Etymology of 凹

Formation typeIdeographic 指事
六书 ClassificationIdeograph (指事字)~2% of characters
Explanation

Pictograph of a concavity. Opposite of 凸.

Memory hint

A rectangle with a hollow

Learn more about Ideograph (指事字) characters
Exercise 1 of 1

Origin

What kind of character is 凹?

Decomposition of 凹

IDS Structure⿱？一
凹Full character
=
一yi1
top
Exercise 1 of 1

Parts

Which of these is part of 凹?

How to say a depression in Chinese

“a depression” in Chinese is凹āo

The character 凹 (āo) refers to a depression or indentation, often describing surfaces that are concave or hollow. It is commonly used in contexts related to physical shapes, such as dips in terrain or objects, and can also denote a sunken or indented appearance.

When to use 凹

It's important to use 凹 in contexts where you specifically describe shapes or surfaces. Common mistakes include confusing it with 窪 (wā), which also refers to a depression but has different applications. Be careful with pronunciation, as misplacing the tone can change the meaning entirely.

凹 or something close to it

凹 (āo) vs 凸 (tū) — choose 凹 when describing a concave shape, while 凸 refers to a convex shape.

What learners get wrong

Learners often confuse 凹 with other characters that describe similar concepts, such as 窪. For example, saying '这个地方很窪' (This place is very concave) is incorrect; instead, use '这个地方很凹'.

Write 凹

凹

Practice writing 凹 stroke by stroke. Watch the animation to learn the stroke order, then try writing it yourself.

Write correctly 3 times to earn XP

Grammar patterns of 凹

凹 functions as an adjective. In Chinese it behaves like a stative verb: place it directly after the subject without 是 (我很高，not 我是高). Use 不 to negate (不高) and pair it with 很 in plain affirmative sentences. It carries 9 related meanings, each with its own usage notes below. The example sentences below show it in action, with practice buttons (Listen, Practice Writing, Practice Speaking) on every line.

Exercise 1 of 4

Fill the gap

Type the missing word. Pinyin works; then pick the character.

他摇摇晃晃地行走在停车场____凸不平的地面上。

He staggered on the uneven surface of the car park.

Example sentences for 凹 (10)

Listen to all sentences once to receive XP
1
他摇摇晃晃地行走在停车场凹凸不平的地面上。

tā yáo yáohuàng huǎng dì xíngzǒu zài tíngchēchǎng āotū bùpíng de dìmiàn shàng。

He staggered on the uneven surface of the car park.
2
柏油路面两边的辅道上布满车辙，凹凸不平。

bǎi yóu lùmiàn liǎngbian de fǔ dào shàng bùmǎn chē chè， āotū bùpíng。

The side tracks off the tarred road were rutted and uneven.
3
墙上仍然有她的子弹留下的凹坑。

qiáng shàng réngrán yǒu tā de zǐdàn liúxia de āo kēng。

The pockmarks made by her bullets are still on the wall.
4
凸凹不平的石墙就像一条很深的运河的河岸。

tū āo bùpíng de dàn qiáng jiù xiàng yī tiáo hěn shēn de yùnhé de hé àn。

The rough rock walls were like the sides of a deep canal.
5
他看起来很年轻，肤色黝黑，五官分明，双颊凹陷。

tā kànqǐlai hěn niánqīng， fū sè yǒu hēi， wǔguān fēnmíng， shuāng jiá āo xiàn。

He looked young, dark and sharp-featured, with hollow cheeks.
6
她看上去又老又瘦,脸颊凹陷,眼圈发黑.

tā kànshangqu yòu lǎo yòu shòu, liǎnjiá āo xiàn, yǎn juān fā hēi.

She looked old and thin with sunken cheeks and hollow eyes.
7
孟岗集洼陷是东濮凹陷内勘探程度最低的地区.

mèng gǎng jí wā xiàn shì dōng pú āo xiàn nèi kāntàn chéngdù zuì dī de dìqū.

Menggangji sag is a region least explored in Dongpu depression.
8
历经发展, 东运已成长中国著名的凹版制版集团企业.

lìjīng fāzhǎn, dōng yùn yǐ chéngzhǎng zhōngguó zhùmíng de āo bǎn zhì bǎn jítuán qǐyè.

After development, the eastern areas have grown famous intaglio printing plate enterprise.
9
留意便宜货，但绝不要买表面凹陷的罐头。

liúyì biànyí huò， dàn jué búyào mǎi biǎomiàn āo xiàn de guàntou。

Watch out for bargains, but never buy dented cans.
10
卡车嘎吱嘎吱地在凹凸不平的地面上颠簸而行。

kǎchē gā zhī gā zhī dì zài āotū bùpíng de dìmiàn shàng diānbǒ ér xíng。

The truck jolted and rattled over the rough ground.

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Word Family of 凹

Compounds2
兕sìa female rhinoceros
垇ào
Words containing this character12
凹āosunken
凹陷āoxiànto cave in
凹槽āocáorecess
凹凸不平āotūbùpínguneven (surface)
凹凸āotūconcave or convex
贾平凹jiǎpíngwāJia Pingwa (1952-), Chinese novelist賈平凹
凹进āojìnconcave凹進
凹坑āokēngcrater
凹版āobǎnintaglio printing plate (or a print made with it)
凹透镜āotòujìngconcave lens凹透鏡
凹面镜āomiànjìngconcave mirror凹面鏡
凹镜āojìngconcave mirror凹鏡
Exercise 1 of 4

Characters with 凹

What does 兕 mean?

Frequently asked questions about 凹

凹 specifically refers to a concave shape, while 窪 describes a depression or hollow that may not be strictly concave.

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