二 - Wiktionary, the free dictionary

二 (Kangxi radical 7, 二+0, 2 strokes, cangjie input 一一 (MM), four-corner 1010₀, composition ⿱一一)

1. Kangxi radical #7, ⼆.
2. Shuowen Jiezi radical №479

• Appendix:Chinese radical/二
• 仁, 𬨜, 𠚧, 况, 元, 𡚬, 示, 忈, 𨳏, 𨴙, 𨶄, 三, 𠓞, 𠮡, 夳, 𦫽, 𫿭, 竺, 𢨑
• 勻, 弍, 𢎥, 𭘾, 𡤾, 𡰥, 𢨧, 𡶂, 𰀁, 𨳎, 冃, 𡆤

Wikisource

• Kangxi Dictionary: page 86, character 1
• Dai Kanwa Jiten: character 247
• Dae Jaweon: page 175, character 6
• Hanyu Da Zidian (first edition): volume 1, page 2, character 1
• Unihan data for U+4E8C

Ideogram (指事) - two parallel strokes. Compare with 一, one stroke meaning one, 三, three strokes meaning three, and 亖 (sì), four strokes meaning four. Duplication of 一 (“one”).

From Proto-Sino-Tibetan *g/s-ni-s. Cognate to Tibetan གཉིས (gnyis), Sikkimese ཉི (nyi), Tangut 𗍫 (*njɨ̱¹), Burmese နှစ် (hnac), and Nuosu ꑍ (nyip). See also: 次 (OC *sn̥ʰis, “second; next”), a cognate within Chinese languages.

二

1. two

   二號線／二号线  ―  èr hào xiàn  ―  line no. 2

   • 子曰：「君子之道，或出或處，或默或語，二人同心，其利斷金。同心之言，其臭如蘭。」 [Classical Chinese, trad.]
     子曰：「君子之道，或出或处，或默或语，二人同心，其利断金。同心之言，其臭如兰。」 [Classical Chinese, simp.]

     From: I Ching, 11^th – 8^th century BCE

     Zǐ yuē: “Jūnzǐ zhī dào, huò chū huò chǔ, huò mò huò yǔ, èr rén tóng xīn, qí lì duàn jīn. Tóng xīn zhī yán, qí xiù rú lán.” [Pinyin]

     The Master said, on this, "The ways of good men (different seem). This in a public office toils; that in his home the time beguiles. One man his lips with silence seals; another all his mind reveals. But when two men are one in heart, not iron bolts keep them apart; the words they in their union use, fragrance like orchid plants diffuse."

2. second

   二哥  ―  èrgē  ―  second elder brother

   • 子墨子曰：國有七患。七患者何？城郭溝池不可守而治宮室，一患也。邊國至境四鄰莫救，二患也。 [Classical Chinese, trad.]
     子墨子曰：国有七患。七患者何？城郭沟池不可守而治宫室，一患也。边国至境四邻莫救，二患也。 [Classical Chinese, simp.]

     From: Mozi, c. 4^th century BCE

     Zǐ Mòzǐ yuē: guó yǒu qī huàn. Qī huàn zhě hé? Chéngguō gōuchí bù kě shǒu ér zhì gōngshì, yī huàn yě. Biānguó zhì jìng sìlín mò jiù, èr huàn yě. [Pinyin]

     Mozi said: There are seven causes of worry to a state and they are: (1) When the outer and the inner city walls are not defensible; (2) When an enemy state is approaching and yet one's neighbours do not come to the rescue.

3. ^† secondary, vice-
4. ^† again, once more
5. ^† two-fold, double
6. ^† fold, times
7. ^† different; other, else

   二意  ―  èryì  ―  (please add an English translation of this usage example)

   二心  ―  èrxīn  ―  (please add an English translation of this usage example)

8. (handwritten, dated, now informal) An iteration mark denoting the repetition of the previous hanzi; often written at a smaller size when used for this purpose.

   Alternative forms: 𠄠 (èr), 𖿣

   Synonyms: 々, 〻

9. Short for "twenty, two hundred or two thousand" after hundreds, thousands and ten thousands.

   ※ Such a definition of a number results from a number's being used without a unit after a quantity with both a value (exists even if hidden) and a unit to indicate the quantity with the value being the number and the unit one grade lower. So does the next definition.

   百二 [Cantonese]  ―  baak³ ji⁶ [Jyutping]  ―  one hundred twenty

   百二 [Hokkien]  ―  pah jī [Pe̍h-ōe-jī]  ―  one hundred twenty

   買電腦花了一千二。 [MSC, trad.]
   买电脑花了一千二。 [MSC, simp.]

   Mǎi diànnǎo huā le yī qiān èr. [Pinyin]

   Buying the computer cost me a thousand and two hundred bucks.

10. Short for "twenty cents".

    黃瓜一塊二一斤。 [MSC, trad.]
    黄瓜一块二一斤。 [MSC, simp.]

    Huángguā yī kuài èr yī jīn. [Pinyin]

    The cucumbers are one dollar twenty per half kilogram.

11. (dialectal Mandarin) stupid, dumb; silly, thick, lacking mental agility (often in a cute way)

    你這人怎麼這麼二！ [MSC, trad.]
    你这人怎么这么二！ [MSC, simp.]

    Nǐ zhè rén zěnme zhème èr! [Pinyin]

    Why are you so incorrigibly stupid!

12. (Hong Kong Cantonese, school slang) to obtain a level two in a subject in DSE (exam) (usually implies failing the subject)

    我中文二咗，入唔到U。 [Cantonese, trad. and simp.]

    ngo⁵ zung¹ man^4-2 ji⁶ zo², jap⁶ m⁴ dou³ ju¹. [Jyutping]

    I got a level two in Chinese, can't get into university.

13. (Classical) Alternative form of 貳／贰 (èr); usually limited to the simplified script

    不二过  ―  bù'èrguò  ―  (please add an English translation of this usage example)

See 兩 - Usage notes.

• (dialectal or used in counting) 兩／两 (liǎng)

Others:

• → Bouyei: ngih
• → Northern Thai: ᨿᩦ᩵
• → Lao: ຍີ່ (nyī)
• → Thai: ยี่ (yîi)
• → Vietnamese: nhì
• → Zhuang: ngeih

二

(First grade kyōiku kanji)

• 弐 (financial or formal)

• Go-on: に (ni, Jōyō)
• Kan-on: じ (ji)
• Tō-on: アル (aru)
• Kun: ふた (futa, 二, Jōyō)、ふたつ (futatsu, 二つ, Jōyō)、ふつ (futsu, 二つ)
• Nanori: おと (oto)、つぐ (tsugu)、つぎ (tsugi)、にい (nī)、は (ha)、ふ (fu)、ふたつ (futatsu)、ふだ (fuda)、わ (wa)

• 二(ふた)つ (futatsu): noun: two, 2 (counting); two years old
• 二(ふた)けた (futaketa) noun: two digits, double figures

From Middle Chinese 二 (ȵiɪ^H, “two”). Compare modern Eastern Min reading nê.

• (Tokyo) に [níꜜ] (Atamadaka – [1])^[1][2]
• IPA^(key): [ɲ̟i]

二(に) • (ni) 

1. two, 2
2. second

   二(に)兎(と)を追(お)う者(もの)は一兎(いっと)をも得(え)ず

   nito o ou mono wa itto o mo ezu

   focus on one thing at a time (literally, “one who chases two rabbits catches neither one”)

   二(に)の足(あし)を踏(ふ)む

   ni no ashi o fumu

   hesitate; think twice (literally, “step on two feet”)

   二(に)階(かい)から目(め)薬(ぐすり)

   nikai kara megusuri

   trying to do an impossible task (literally, “(taking) eye medicine from the second floor”)

二(に) • (ni) 

1. two, 2

Originally /huta/: *[puta] > [ɸuta]. The ablaut form of 一 (hito2, “one”), which it doubles.

From Old Japanese, from Proto-Japonic *puta. Cognate with Japanese 双(ふた) (futa).

• (Tokyo) ふた [fùtáꜜ] (Odaka – [2])^[1]
• IPA^(key): [ɸɯ̟ta̠]

二(ふた) • (futa) 

1. two

Borrowing from Mandarin 二 (èr).

• (Tokyo) アル [áꜜrù] (Atamadaka – [1])^[1]
• IPA^(key): [a̠ɾɯ̟]

二(アル) • (aru) 

1. two, 2

• 一(イー) (ī)
• 三(サン) (san)
• 四(スー) (sū)

From Middle Chinese 二 (MC nyijH).

• (SK Standard/Seoul) IPA^(key): [i(ː)]
• Phonetic hangul: [이(ː)]
  • Though still prescribed in Standard Korean, most speakers in both Koreas no longer distinguish vowel length.

Wikisource

二 (eumhun 두 이 (du i))

1. hanja form^? of 이 (“two”)

• 국제퇴계학회 대구경북지부 (國際退溪學會 大邱慶北支部) (2007). Digital Hanja Dictionary, 전자사전／電子字典. [2]

二: Hán Việt readings: nhị^[1][2][3]
二: Nôm readings: nhì^[1][2][3], nhị^[2][3][4], nhẹ^[1]

1. chữ Hán form of nhị (“two”).
2. Nôm form of nhì (“second”).

二

1. Sawndip form of ngeih