# 洞

| 洞 | U+6D1E, &#27934; CJK UNIFIED IDEOGRAPH-6D1E |
| ← 洝 [U+6D1D] | CJK Unified Ideographs | 洟 → [U+6D1F] |
| 洞 | U+FA05, &#64005; CJK COMPATIBILITY IDEOGRAPH-FA05 |
| ← 宅 [U+FA04] | CJK Compatibility Ideographs | 暴 → [U+FA06] |

## Translingual
### Han character

洞 (Kangxi radical 85, 水+6, 9 strokes, cangjie input 水月一口 (EBMR), four-corner 3712$_0$, composition ⿰氵同)

#### Derived characters

* 霘, 𪔦, 𢞉

#### References

* Kangxi Dictionary: page 620, character 18
* Dai Kanwa Jiten: character 17386
* Dae Jaweon: page 1016, character 7
* Hanyu Da Zidian (first edition): volume 3, page 1607, character 3
* Unihan data for U+6D1E
* Unihan data for U+FA05

## Chinese
### Glyph origin

* Historical forms of the character 洞
* Shuowen Jiezi (compiled in Han)
* Small seal script
| | Old Chinese |
| 鮦 | *duʔ, *doːŋ, *doŋʔ |
| 侗 | *tʰoːŋ, *tʰoːŋʔ, *doːŋ |
| 恫 | *tʰoːŋ, *doːŋs |
| 痌 | *tʰoːŋ |
| 同 | *doːŋ |
| 仝 | *zlon, *doːŋ |
| 銅 | *doːŋ |
| 桐 | *doːŋ |
| 峒 | *doːŋ, *doːŋs |
| 硐 | *doːŋ, *doːŋʔ |
| 筒 | *doːŋ, *doːŋs |
| 洞 | *doːŋ, *doːŋs |
| 烔 | *doːŋ |
| 挏 | *doːŋ, *doːŋʔ |
| 酮 | *doːŋ, *doːŋʔ |
| 鲖 |
| 眮 | *doːŋ, *doːŋʔ, *doːŋs |
| 衕 | *doːŋ, *doːŋs |
| 哃 | *doːŋ |
| 絧 | *doːŋ, *doːŋs |
| 姛 | *doːŋʔ |
| 詷 | *doːŋʔ, *doːŋs |
| 胴 | *doːŋs |
| 駧 | *doːŋs |
| 迵 | *doːŋs |
| 戙 | *doːŋs |
Phono-semantic compound (形聲 / 形声, OC *doːŋ, *doːŋs): semantic 水 (“water”) + phonetic 同 (OC *doːŋ).

### Etymology
#### “hole; cavity” > “penetrating; thorough; zero”

    From Proto-Sino-Tibetan *dwa(ː)ŋ (“hole; orifice; cave; pit; well”). Cognate with Burmese တွင်း (twang:), Tibetan དོང (dong, “deep hole; pit”) and Jingpho kha-thung (“well, pit”).

### Pronunciation 1

* Mandarin
    (Standard)
       (Pinyin): dòng (dong$^4$)
       (Zhuyin): ㄉㄨㄥˋ
    (Chengdu, Sichuanese Pinyin): dong$^4$
    (Dungan, Cyrillic and Wiktionary): дун (dun, III)
* Cantonese
    (Guangzhou–Hong Kong, Jyutping): dung$^6$ / dung$^{6-2}$
    (Taishan, Wiktionary): uung$^5$
* Gan (Wiktionary): tung$^5$
* Hakka
    (Sixian, PFS): thung
    (Meixian, Guangdong): tung$^4$
* Jin (Wiktionary): dung$^3$
* Northern Min (KCR): dō̤ng
* Eastern Min (BUC): dâe̤ng
* Southern Min
    (Hokkien, POJ): tōng / tāng
    (Teochew, Peng'im): dang$^7$ / tong$^7$
* Wu (Northern, Wugniu): $^6$don
* Xiang (Changsha, Wiktionary): dong$^4$ / dong$^5$
* Mandarin
** (Standard Chinese)
*** Hanyu Pinyin: dòng
*** Zhuyin: ㄉㄨㄥˋ
*** Tongyong Pinyin: dòng
*** Wade–Giles: tung$^4$
*** Yale: dùng
*** Gwoyeu Romatzyh: donq
*** Palladius: дун (dun)
*** Sinological IPA : /tʊŋ⁵¹/
** (Chengdu)
*** Sichuanese Pinyin: dong$^4$
*** Scuanxua Ladinxua Xin Wenz: dung
*** Sinological IPA : /toŋ²¹³/
** (Dungan)
*** Cyrillic and Wiktionary: дун (dun, III)
*** Sinological IPA : /tuŋ⁴⁴/
    (Note: Dungan pronunciation is currently experimental and may be inaccurate.)
* Cantonese
** (Standard Cantonese, Guangzhou–Hong Kong)
*** Jyutping: dung$^6$ / dung$^{6-2}$
*** Yale: duhng / dúng
*** Cantonese Pinyin: dung$^6$ / dung$^{6-2}$
*** Guangdong Romanization: dung$^6$ / dung$^{6-2}$
*** Sinological IPA : /tʊŋ²²/, /tʊŋ²²⁻³⁵/
** (Taishanese, Taicheng)
*** Wiktionary: uung$^5$
*** Sinological IPA : /ɵŋ³²/
* Gan
** (Nanchang)
*** Wiktionary: tung$^5$
*** Sinological IPA : /tʰuŋ¹¹/
* Hakka
** (Sixian, incl. Miaoli and Neipu)
*** Pha̍k-fa-sṳ: thung
*** Hakka Romanization System: tung
*** Hagfa Pinyim: tung$^4$
*** Sinological IPA: /tʰuŋ⁵⁵/
** (Meixian)
*** Guangdong: tung$^4$
*** Sinological IPA: /tʰʊŋ⁵³/
* Jin
** (Taiyuan)
*** Wiktionary: dung$^3$
*** Sinological IPA (old-style): /tuŋ⁴⁵/
* Northern Min
** (Jian'ou)
*** Kienning Colloquial Romanized: dō̤ng
*** Sinological IPA : /tɔŋ⁵⁵/
* Eastern Min
** (Fuzhou)
*** Bàng-uâ-cê: dâe̤ng
*** Sinological IPA : /tɔyŋ²⁴²/
* Southern Min
** (Hokkien: Xiamen, Quanzhou, Zhangzhou, Jinjiang, General Taiwanese)
*** Pe̍h-ōe-jī: tōng
*** Tâi-lô: tōng
*** Phofsit Daibuun: dong
*** IPA (Quanzhou, Jinjiang): /tɔŋ⁴¹/
*** IPA (Xiamen, Zhangzhou): /tɔŋ²²/
*** IPA (Taipei, Kaohsiung): /tɔŋ³³/
** (Hokkien: Xiamen, Zhangzhou)
*** Pe̍h-ōe-jī: tāng
*** Tâi-lô: tāng
*** Phofsit Daibuun: dang
*** IPA (Xiamen, Zhangzhou): /taŋ²²/
** (Teochew)
*** Peng'im: dang$^7$ / tong$^7$
*** Pe̍h-ōe-jī-like: tāng / thōng
*** Sinological IPA : /taŋ¹¹/, /tʰoŋ¹¹/
* dang7 - vernacular;
* tong7 - literary.
* Dialectal data
| Variety | Location | edit洞 |
| Mandarin | Beijing | /tuŋ⁵¹/ |
| Mandarin | Harbin | /tuŋ⁵³/ |
| Mandarin | Tianjin | /tuŋ⁵³/ |
| Mandarin | Jinan | /tuŋ²¹/ |
| Mandarin | Qingdao | /təŋ⁴²/ |
| Mandarin | Zhengzhou | /tuŋ³¹²/ |
| Mandarin | Xi'an | /tuŋ⁴⁴/ |
| Mandarin | Xining | /tuə̃²¹³/ |
| Mandarin | Yinchuan | /tuŋ¹³/ |
| Mandarin | Lanzhou | /tũn¹³/ |
| Mandarin | Ürümqi | /tuŋ²¹³/ |
| Mandarin | Wuhan | /toŋ³⁵/ |
| Mandarin | Chengdu | /toŋ¹³/ |
| Mandarin | Guiyang | /toŋ²¹³/ |
| Mandarin | Kunming | /toŋ¹/ |
| Mandarin | Nanjing | /toŋ⁴⁴/ |
| Mandarin | Hefei | /təŋ²¹/ |
| Jin | Taiyuan | /tuəŋ⁴⁵/ |
| Jin | Pingyao | /tuŋ³⁵/ |
| Jin | Hohhot | /tũŋ⁵⁵/ |
| Wu | Shanghai | /doŋ²³/ |
| Wu | Suzhou | /doŋ³¹/ |
| Wu | Hangzhou | /doŋ¹³/ |
| Wu | Wenzhou | /doŋ²²/ |
| Hui | Shexian | /tʰʌ̃²²/ |
| Hui | Tunxi | /tan¹¹/ |
| Xiang | Changsha | /toŋ⁵⁵/ /toŋ¹¹/ |
| Xiang | Xiangtan | /dən²¹/ |
| Gan | Nanchang | /tʰuŋ²¹/ |
| Hakka | Meixian | /tʰuŋ⁵³/ |
| Hakka | Taoyuan | /tʰuŋ⁵⁵/ |
| Cantonese | Guangzhou | /toŋ²²/ |
| Cantonese | Nanning | /tuŋ²²/ |
| Cantonese | Hong Kong | /tuŋ²²/ |
| Min | Xiamen (Hokkien) | /tɔŋ²²/ |
| Min | Fuzhou (Eastern Min) | /tɔyŋ²⁴²/ |
| Min | Jian'ou (Northern Min) | /tɔŋ⁴⁴/ |
| Min | Shantou (Teochew) | /taŋ³¹/ |
| Min | Haikou (Hainanese) | /ʔdoŋ³³/ /ʔdoŋ²³/ ～房 |
* Middle Chinese: duwngH
Rime :
| Character | 洞 |
| Reading # | 2/2 |
| Initial (聲) | 定 (7) |
| Final (韻) | 東 (1) |
| Tone (調) | Departing (H) |
| Openness (開合) | Open |
| Division (等) | I |
| Fanqie | 徒弄切 |
| Baxter | duwngH |
| Reconstructions ||
| Zhengzhang Shangfang | /duŋ$^H$/ |
| Pan Wuyun | /duŋ$^H$/ |
| Shao Rongfen | /duŋ$^H$/ |
| Edwin Pulleyblank | /dəwŋ$^H$/ |
| Li Rong | /duŋ$^H$/ |
| Wang Li | /duŋ$^H$/ |
| Bernhard Karlgren | /dʱuŋ$^H$/ |
| Expected Mandarin Reflex | dòng |
| Expected Cantonese Reflex | dung$^6$ |
* Old Chinese
    (Zhengzhang): /*doːŋs/
Zhengzhang system (2003) :
| Character | 洞 |
| Reading # | 2/2 |
| No. | 12469 |
| Phonetic component | 同 |
| Rime group | 東 |
| Rime subdivision | 0 |
| Corresponding MC rime | 洞 |
| Old Chinese | /*doːŋs/ |

#### Definitions

洞
* hole; cavity; cave
* (literary, or in compounds) thorough; penetrating
* the numeral zero (used in radio communications in aviation and by the military)
* dong, a submunicipal administrative division in North and South Korea

##### Synonyms

* (hole):
| Variety | Location | Words |
| Classical Chinese | Classical Chinese | 孔, 洞, 穴 |
| Formal (Written Standard Chinese) | Formal (Written Standard Chinese) | 孔, 洞, 孔洞, 空洞, 空穴, 窿 |
| Northeastern Mandarin | Beijing | 窟窿 |
| Northeastern Mandarin | Singapore | 洞 |
| Jilu Mandarin | Jinan | 窟窿 |
| Central Plains Mandarin | Luoyang | 窟窿 |
| Central Plains Mandarin | Wanrong | 窟窿 |
| Central Plains Mandarin | Xi'an | 窟窿子, 窟窿 |
| Southwestern Mandarin | Chengdu | 窟窿, 洞洞, 洞 |
| Southwestern Mandarin | Wuhan | 窟窿, 窟眼, 洞洞, 洞 |
| Southwestern Mandarin | Liuzhou | 窿 |
| Jianghuai Mandarin | Nanjing | 窟窿 |
| Jianghuai Mandarin | Yangzhou | 洞, 窟窿 |
| Jianghuai Mandarin | Hefei | 窟窿, 洞 |
| Cantonese | Guangzhou | 窿, 咕窿 |
| Cantonese | Hong Kong | 窿, 咕窿 |
| Cantonese | Taishan | 孔 |
| Cantonese | Yangjiang | 窿 |
| Cantonese | Kuala Lumpur (Guangfu) | 窿 |
| Cantonese | Singapore (Guangfu) | 窿 |
| Gan | Nanchang | 洞 |
| Hakka | Meixian | 窿仔, 窿空仔 |
| Hakka | Miaoli (N. Sixian) | 空 |
| Hakka | Pingtung (Neipu; S. Sixian) | 空 |
| Hakka | Hsinchu County (Zhudong; Hailu) | 空 |
| Hakka | Taichung (Dongshi; Dabu) | 空 |
| Hakka | Hsinchu County (Qionglin; Raoping) | 空 |
| Hakka | Yunlin (Lunbei; Zhao'an) | 空 |
| Jin | Taiyuan | 窟窿, 窟子 |
| Northern Min | Jian'ou | 川 |
| Eastern Min | Fuzhou | 空空 |
| Southern Min | Xiamen | 空, 空口 |
| Southern Min | Quanzhou | 空 |
| Southern Min | Zhangzhou | 空口 |
| Southern Min | Zhangzhou (Changtai) | 空 |
| Southern Min | Taipei | 空 |
| Southern Min | Penang (Hokkien) | 空 |
| Southern Min | Singapore (Hokkien) | 空 |
| Southern Min | Manila (Hokkien) | 空 |
| Southern Min | Chaozhou | 空 |
| Southern Min | Jieyang | 空, 洞 |
| Southern Min | Haifeng | 空 |
| Southern Min | Singapore (Teochew) | 空 |
| Southern Min | Singapore (Hainanese) | 空 |
| Southern Pinghua | Nanning (Tingzi) | 窿 |
| Wu | Suzhou | 洞 |
| Wu | Wenzhou | 洞, 窟, 窟窿 |
| Wu | Jinhua | 窟窿 |
| Xiang | Changsha | 洞, 洞子 |
| Xiang | Shuangfeng | 眼貢, 洞 |
* (zero):
| Variety | Location | Words |
| Formal (Written Standard Chinese) | Formal (Written Standard Chinese) | 零, 洞 as a digit |
| Northeastern Mandarin | Beijing | 零 |
| Northeastern Mandarin | Taiwan | 零 |
| Northeastern Mandarin | Harbin | 零 |
| Northeastern Mandarin | Malaysia | 零 |
| Northeastern Mandarin | Singapore | 零 |
| Jilu Mandarin | Jinan | 零 |
| Jiaoliao Mandarin | Yantai (Muping) | 零 |
| Central Plains Mandarin | Luoyang | 零 |
| Central Plains Mandarin | Xi'an | 零 |
| Central Plains Mandarin | Xining | 零 |
| Central Plains Mandarin | Xuzhou | 零 |
| Lanyin Mandarin | Yinchuan | 零 |
| Lanyin Mandarin | Lanzhou | 零 |
| Lanyin Mandarin | Ürümqi | 零 |
| Southwestern Mandarin | Chengdu | 零 |
| Southwestern Mandarin | Wuhan | 零 |
| Southwestern Mandarin | Guiyang | 零 |
| Southwestern Mandarin | Liuzhou | 零 |
| Jianghuai Mandarin | Nanjing | 零 |
| Jianghuai Mandarin | Yangzhou | 零 |
| Cantonese | Guangzhou | 零 |
| Cantonese | Hong Kong | 零 |
| Cantonese | Macau | 零 |
| Cantonese | Dongguan | 零 |
| Cantonese | Kuala Lumpur (Guangfu) | 零 |
| Cantonese | Singapore (Guangfu) | 零 |
| Gan | Lichuan | 零 |
| Gan | Pingxiang | 零 |
| Hakka | Meixian | 零 |
| Hakka | Yudu | 零 |
| Hakka | Miaoli (N. Sixian) | 零 |
| Hakka | Pingtung (Neipu; S. Sixian) | 零 |
| Hakka | Hsinchu County (Zhudong; Hailu) | 零 |
| Hakka | Taichung (Dongshi; Dabu) | 零 |
| Hakka | Hsinchu County (Qionglin; Raoping) | 零 |
| Hakka | Yunlin (Lunbei; Zhao'an) | 零 |
| Huizhou | Jixi | 零 |
| Jin | Taiyuan | 零 |
| Jin | Xinzhou | 零 |
| Northern Min | Jian'ou | 零 |
| Eastern Min | Fuzhou | 零, 環 |
| Southern Min | Xiamen | 空, 零 |
| Southern Min | Quanzhou | 空 |
| Southern Min | Zhangzhou | 空 |
| Southern Min | Taipei | 空 |
| Southern Min | Kaohsiung | 空 |
| Southern Min | Tainan | 空 |
| Southern Min | Penang (Hokkien) | 空 |
| Southern Min | Singapore (Hokkien) | 空 |
| Southern Min | Manila (Hokkien) | 空 |
| Southern Min | Chaozhou | 空 |
| Southern Min | Shantou | 空 |
| Southern Min | Singapore (Teochew) | 空 |
| Southern Min | Batam (Teochew) | 空 |
| Southern Min | Leizhou | 零 |
| Southern Min | Wenchang | 空, 零 |
| Southern Min | Haikou | 空, 零 |
| Southern Pinghua | Nanning (Tingzi) | 零 |
| Wu | Shanghai | 零 |
| Wu | Shanghai (Chongming) | 零 |
| Wu | Suzhou | 零 |
| Wu | Hangzhou | 零 |
| Wu | Ningbo | 零 |
| Wu | Wenzhou | 零 |
| Wu | Jinhua | 零 |

#### Compounds

* 三洞
* 上洞人
* 九曲洞
* 仙洞
* 八洞
* 函洞 (hándòng)
* 別有洞天 / 别有洞天 (biéyǒudòngtiān)
* 勿里洞島
* 千佛洞
* 地洞 (dìdòng)
* 坑洞 (kēngdòng)
* 塞狗洞
* 大洞果
* 山洞 (shāndòng)
* 山頂洞人 / 山顶洞人
* 岩洞 (yándòng)
* 拖牢洞
* 挖洞
* 掘洞
* 晶洞 (jīngdòng)
* 曹洞宗
* 月洞
* 月洞門 / 月洞门
* 橋洞 / 桥洞 (qiáodòng)
* 水簾洞 / 水帘洞
* 法律漏洞
* 洞中肯綮
* 洞仙 (dòngxiān)
* 洞兒 / 洞儿
* 洞壑
* 洞天 (dòngtiān)
* 洞天福地
* 洞如觀火 / 洞如观火 (dòngrúguānhuǒ)
* 洞宮 / 洞宫
* 洞家
* 洞察 (dòngchá)
* 洞察其奸
* 洞察機先 / 洞察机先
* 洞居
* 洞府
* 洞庭 (dòngtíng)
* 洞庭湖 (Dòngtíng Hú)
* 洞徹 / 洞彻
* 洞悉 (dòngxī)
* 洞悉明白
* 洞悉真相
* 洞戶 / 洞户
* 洞房 (dòngfáng)
* 洞房花燭 / 洞房花烛
* 洞明
* 洞曉 / 洞晓
* 洞氣 / 洞气
* 洞洞
* 洞然
* 洞燭 / 洞烛
* 洞燭入微 / 洞烛入微
* 洞燭其奸
* 洞燭姦邪 / 洞烛奸邪
* 洞燭機先 / 洞烛机先
* 洞穴 (dòngxué)
* 洞穿
* 洞窟 (dòngkū)
* 洞窟美術 / 洞窟美术
* 洞簫 / 洞箫 (dòngxiāo)
* 洞若觀火 / 洞若观火 (dòngruòguānhuǒ)
* 洞螈 (dòngyuán)
* 洞見 / 洞见 (dòngjiàn)
* 洞見癥結 / 洞见症结
* 洞貫 / 洞贯
* 洞達 / 洞达
* 洞鑒 / 洞鉴
* 洞鑒古今 / 洞鉴古今
* 洞門 / 洞门
* 洞開 / 洞开 (dòngkāi)
* 涵洞 (hándòng)
* 漏洞 (lòudòng)
* 漏洞百出 (lòudòngbǎichū)
* 潘洞
* 潮音洞
* 炕洞
* 無底洞 / 无底洞 (wúdǐdòng)
* 狗洞
* 甕洞兒 / 瓮洞儿
* 白洞 (báidòng)
* 白鹿洞
* 石洞 (Shídòng)
* 石灰岩洞
* 破洞 (pòdòng)
* 福地洞天
* 空洞 (kōngdòng)
* 空空洞洞
* 窗洞 (chuāngdòng)
* 窯洞 / 窑洞 (yáodòng)
* 花兒洞子 / 花儿洞子
* 花燭洞房 / 花烛洞房
* 芭蕉洞 (bājiāodòng)
* 通幽洞微
* 連闥洞房 / 连闼洞房
* 鐘乳洞 / 钟乳洞
* 鑽天打洞 / 钻天打洞
* 鑽狗洞 / 钻狗洞
* 門洞 / 门洞
* 防空洞 (fángkōngdòng)
* 風洞 / 风洞
* 鬧洞房 / 闹洞房 (nào dòngfáng)
* 鬼窟洞
* 黃金洞 / 黄金洞 (Huángjīndòng)
* 黑洞 (hēidòng)
* 黑洞洞 (hēidòngdòng)
* 龍洞 / 龙洞

### Pronunciation 2

* Mandarin
    (Pinyin): tóng (tong$^2$)
    (Zhuyin): ㄊㄨㄥˊ
* Cantonese (Jyutping): tung$^4$
* Mandarin
** (Standard Chinese)
*** Hanyu Pinyin: tóng
*** Zhuyin: ㄊㄨㄥˊ
*** Tongyong Pinyin: tóng
*** Wade–Giles: tʻung$^2$
*** Yale: túng
*** Gwoyeu Romatzyh: torng
*** Palladius: тун (tun)
*** Sinological IPA : /tʰʊŋ³⁵/
* Cantonese
** (Standard Cantonese, Guangzhou–Hong Kong)
*** Jyutping: tung$^4$
*** Yale: tùhng
*** Cantonese Pinyin: tung$^4$
*** Guangdong Romanization: tung$^4$
*** Sinological IPA : /tʰʊŋ²¹/
* Middle Chinese: duwng
Rime :
| Character | 洞 |
| Reading # | 1/2 |
| Initial (聲) | 定 (7) |
| Final (韻) | 東 (1) |
| Tone (調) | Level (Ø) |
| Openness (開合) | Open |
| Division (等) | I |
| Fanqie | 徒紅切 |
| Baxter | duwng |
| Reconstructions ||
| Zhengzhang Shangfang | /duŋ/ |
| Pan Wuyun | /duŋ/ |
| Shao Rongfen | /duŋ/ |
| Edwin Pulleyblank | /dəwŋ/ |
| Li Rong | /duŋ/ |
| Wang Li | /duŋ/ |
| Bernhard Karlgren | /dʱuŋ/ |
| Expected Mandarin Reflex | tóng |
| Expected Cantonese Reflex | tung$^4$ |
* Old Chinese
    (Zhengzhang): /*doːŋ/
Zhengzhang system (2003) :
| Character | 洞 |
| Reading # | 1/2 |
| No. | 12453 |
| Phonetic component | 同 |
| Rime group | 東 |
| Rime subdivision | 0 |
| Corresponding MC rime | 同 |
| Old Chinese | /*doːŋ/ |

#### Definitions

洞
* Only used in 澒洞／𭱊洞 (hòngtóng) and 洪洞 (Hóngtóng, “Hongtong”).

### References

* “洞”, in 漢語多功能字庫 (Multi-function Chinese Character Database)‎, 香港中文大學 (the Chinese University of Hong Kong), 2014–

## Japanese
### Kanji

(Jōyō kanji)
* cave, den, grotto

#### Readings

* Go-on: ずう (zū)
* Kan-on: とう (tō)
* Kan’yō-on: どう (dō, Jōyō)
* Kun: うつろ (utsuro, 洞)、うつろ (utsuro, 洞ろ)、ふかい (fukai)、ほがらか (hogaraka)、ほら (hora, 洞, Jōyō)、みぬく (minuku)

#### Compounds

* 洞窟(どうくつ) (dōkutsu)
* 洞察(どうさつ) (dōsatsu)
* 洞簫(どうしょう) (dōshō): xiao (Chinese flute)

### Etymology

* Kanji in this term
* 洞
* うつろ Grade: S
* kun'yomi
For pronunciation and definitions of 洞 – see the following entry. :
| 【虚うつろ】 | [adjective] hollow; empty; vacant; devoid of contents [adjective] (figuratively) hollow; empty; vacant; lifeless [noun] emptiness; vacancy; hollow; void; cavity [noun] (figuratively) emptiness; vacancy; hollow; void; hole; cavity Alternative spellings 空ろ, 洞ろ |
(This term, 洞, is an alternative spelling (rare) of the above term.) :

## Korean
### Etymology 1

From Middle Chinese 洞 (MC duwngH).
* Recorded as Middle Korean 또ᇰ〮 (Yale: ttwóng) in Dongguk Jeongun (東國正韻 / 동국정운), 1448.
* Recorded as Middle Korean 동 (twong)$^訓$ (Yale: twong) in Sinjeung Yuhap (新增類合 / 신증유합), 1576.

#### Pronunciation

* (SK Standard/Seoul) IPA: [to̞(ː)ŋ]
* Phonetic hangul: [동(ː)]
** Though still prescribed in Standard Korean, most speakers in both Koreas no longer distinguish vowel length.

#### Hanja

Wikisource 洞 (eumhun 골 동 (gol dong))
* hanja form of 동 (“hole; cavity; cave”)
* hanja form of 동 (“dong, a submunicipal administrative division in North and South Korea”)

#### Compounds

* 공동(空洞) (gongdong)
* 대동(大洞) (Daedong)
* 동굴(洞窟) (donggul)
* 동내(洞內) (dongnae)
* 동내방내(洞內坊內) (dongnaebangnae)
* 동리(洞里) (dongni)
* 동문(洞門) (dongmun)
* 동방(洞房) (dongbang)
* 동장(洞長) (dongjang)

### Etymology 2

From a corrupted or unorthodox reading.

#### Pronunciation

* (SK Standard/Seoul) IPA: [tʰo̞(ː)ŋ]
* Phonetic hangul: [통(ː)]
** Though still prescribed in Standard Korean, most speakers in both Koreas no longer distinguish vowel length.

#### Hanja

洞 (eumhun 밝을 통 (balgeul tong))
* hanja form of 통 (“bright; thorough; penetrating”)

#### Compounds

* 통견(洞見) (tonggyeon)
* 통달(洞達) (tongdal)
* 통찰(洞察) (tongchal)
* 통촉(洞燭) (tongchok)

### References

* 국제퇴계학회 대구경북지부 (國際退溪學會 大邱慶北支部) (2007). Digital Hanja Dictionary, 전자사전／電子字典.

## Vietnamese
### Han character

洞: Hán Nôm readings: đọng, động, đùng, dộng, dọng, đỗng
* This term needs a translation to English. Please help out and add a translation, then remove the text {{rfdef}}.