井

井 (Kangxi radical 7, 二+2, 4 strokes, cangjie input 廿廿 (TT), four-corner 5500₀, composition ⿻一廾)

• 㘫, 妌, 𪪁, 汫, 阱, 𪰉, 肼, 㐩, 𭾠, 畊, 𮈃, 𬙍, 耕, 䎴, 𬟷, 𮗻, 𬪦, 㓝, 刱, 𫡳, 𫎁, 宑, 𬜣, 𬼾, 𭾞, 穽, 𬆓, 䨍, 坓, 汬, 丼, 𬑽, 囲
• 𰃖, 进, 讲 (Simplified from 進 and 講)

• ヰ (Katakana character derived from Man'yōgana)

• Kangxi Dictionary: page 86, character 14
• Dai Kanwa Jiten: character 258
• Dae Jaweon: page 183, character 1
• Hanyu Da Zidian (first edition): volume 1, page 10, character 4
• Unihan data for U+4E95

Historical forms of the character 井
Shang	Western Zhou	Warring States	Shuowen Jiezi (compiled in Han)	Liushutong (compiled in Ming)
Oracle bone script	Bronze inscriptions	Chu slip and silk script	Small seal script	Transcribed ancient scripts
Oracle bone script j12550 j12551 j12552 j12553 j12554 j12555 j12556 j12557 j12558 j12559 j12560 j12561 j12562 j12563 j12564 j12565 j12566 j12567 j12568 j12569 j12570 j12571 j12572 j12573 j12574 j12575 Bronze inscriptions b07748 b07749 b07750 b07751 b07752 b07753 b07754 b07755 b07757 b07758 b07759 b07760 b07761 b07762 b07763 b07764 b07765 b07766 b07767 b07768 b07769 b07770 b07771 b07772 b07773 b07774 b07775 b07776 b07777 b07778 b07779 b07780 Small seal script s03663 Transcribed ancient scripts L17889 L17890 L17891 L17892
References: Mostly from Richard Sears' Chinese Etymology site (authorisation), which in turn draws data from various collections of ancient forms of Chinese characters, including: Shuowen Jiezi (small seal), Jinwen Bian (bronze inscriptions), Liushutong (Liushutong characters) and Yinxu Jiaguwen Bian (oracle bone script).

井 – an old well in a historic area in Shenzhen. Notice the square shape.

Pictogram (象形) – a square well, with supports on four sides.

Some forms have a stone inside the well, as in 丼.

井

1. well (a hole sunk into the ground) (Classifier: 口; 眼)
2. well-shaped object; mineshaft, pit
3. hometown
4. neat; tidy

   井井有條／井井有条  ―  jǐngjǐngyǒutiáo  ―  neat and tidy

5. 48th hexagram of the I Ching
6. a surname

(common “Jōyō” kanji)

1. well

• Go-on: しょう (shō, Jōyō ^†)^{←しやう (syau, historical)}
• Kan-on: せい (sei, Jōyō)
• Kun: い (i, 井, Jōyō)^{←ゐ (wi, 井, historical)}; いど (ido, 井)^{←ゐど (wido, 井, historical)}

wi > i.

• (Tokyo) い​ [íꜜ] (Atamadaka – [1])[1][2]
• IPA^(key): [i]

井(い) • (i) ^{←ゐ (wi)?}

1. well (water source)

• 井(い)の中(なか)の蛙(かわず)大海(たいかい)を知(し)らず (i no naka no kawazu taikai o shirazu): metaphor of a narrow world view based on limited experience (literally, "a frog in a well does not know the great ocean")

井(い) • (I) 

1. a surname

From Middle Chinese 井 (tsjeng^X).

• (Tokyo) せ​ー [séꜜè] (Atamadaka – [1])[1]
• IPA^(key): [se̞ː]

井(せい) • (sei) 

1. well, well curb
2. Well (Chinese constellation)

From Middle Chinese 井 (MC tsjengX). Recorded as Middle Korean 져ᇰ〯 (cyěng) (Yale: cyeng) in Hunmong Jahoe (訓蒙字會 / 훈몽자회), 1527.

Wikisource 井 (eumhun 우물 정 (umul jeong))

1. Hanja form^? of 정 (“well (a hole sunk into the ground)”).

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

井: Hán Nôm readings: tỉnh

1. This term needs a translation to English. Please help out and add a translation, then remove the text {{rfdef}}.