# 理由
## Chinese
### Etymology

Wasei kango (和製漢語), orthographically borrowed from Japanese 理(り)由(ゆう) (riyū).

### Pronunciation

* Mandarin
    (Pinyin): lǐyóu
    (Zhuyin): ㄌㄧˇ ㄧㄡˊ
* Cantonese (Jyutping): lei$^5$ jau$^4$
* Hakka (Sixian, PFS): lî-yù
* Southern Min
    (Hokkien, POJ): lí-iû
    (Teochew, Peng'im): li$^2$ iu$^5$
* Mandarin
** (Standard Chinese)
*** Hanyu Pinyin: lǐyóu
*** Zhuyin: ㄌㄧˇ ㄧㄡˊ
*** Tongyong Pinyin: lǐyóu
*** Wade–Giles: li$^3$-yu$^2$
*** Yale: lǐ-yóu
*** Gwoyeu Romatzyh: liiyou
*** Palladius: лию (liju)
*** Sinological IPA : /li²¹⁴⁻²¹ joʊ̯³⁵/
** (Standard Chinese, erhua-ed) (理由兒／理由儿)
*** Hanyu Pinyin: lǐyóur
*** Zhuyin: ㄌㄧˇ ㄧㄡˊㄦ
*** Tongyong Pinyin: lǐyóur
*** Wade–Giles: li$^3$-yu$^2$-ʼrh
*** Yale: lǐ-yóur
*** Gwoyeu Romatzyh: liiyoul
*** Palladius: лиюр (lijur)
*** Sinological IPA : /li²¹⁴⁻²¹ jɤʊ̯ɻʷ³⁵/
* Cantonese
** (Standard Cantonese, Guangzhou–Hong Kong)
*** Jyutping: lei$^5$ jau$^4$
*** Yale: léih yàuh
*** Cantonese Pinyin: lei$^5$ jau$^4$
*** Guangdong Romanization: léi$^5$ yeo$^4$
*** Sinological IPA : /lei̯¹³ jɐu̯²¹/
* Hakka
** (Northern Sixian, incl. Miaoli)
*** Pha̍k-fa-sṳ: lî-yù
*** Hakka Romanization System: li$^ˊ$ iu$^ˇ$
*** Hagfa Pinyim: li$^1$ yiu$^2$
*** Sinological IPA: /li²⁴ i̯u¹¹/
** (Southern Sixian, incl. Neipu)
*** Pha̍k-fa-sṳ: lî-yù
*** Hakka Romanization System: li$^ˊ$ (r)iu$^ˇ$
*** Hagfa Pinyim: li$^1$ yiu$^2$
*** Sinological IPA: /li²⁴ (j)i̯u¹¹/
* Southern Min
** (Hokkien)
*** Pe̍h-ōe-jī: lí-iû
*** Tâi-lô: lí-iû
*** Phofsit Daibuun: lyiuu
*** IPA (Xiamen): /li⁵³⁻⁴⁴ iu²⁴/
*** IPA (Quanzhou): /li⁵⁵⁴⁻²⁴ iu²⁴/
*** IPA (Zhangzhou): /li⁵³⁻⁴⁴ iu¹³/
*** IPA (Taipei): /li⁵³⁻⁴⁴ iu²⁴/
*** IPA (Kaohsiung): /li⁴¹⁻⁴⁴ iu²³/
** (Teochew)
*** Peng'im: li$^2$ iu$^5$
*** Pe̍h-ōe-jī-like: lí iû
*** Sinological IPA : /li⁵²⁻³⁵ iu⁵⁵/

### Noun

理由
* reason; grounds; justification

#### Synonyms

* 來由／来由 (láiyóu)
* 原因 (yuányīn)
* 因由 (yīnyóu)
* 因端 (Hokkien)
* 因致端 (Hokkien)
* 基因 (jīyīn) (dated)
* 張本／张本 (zhāngběn) (literary)
* 成因 (chéngyīn)
* 所以然 (suǒyǐrán)
* 根由 (gēnyóu)
* 緣故／缘故 (yuángù)
* 緣由／缘由 (yuányóu)
* 緣起／缘起 (yuánqǐ)
* 肇因 (zhàoyīn)
* 言因 (Anxi Hokkien)
* 說道／说道 (shuōdao) (colloquial)
* 起因 (qǐyīn)
* 道理 (dàolǐ)
* 關係／关系

### References

* ↑ 汉语外来词词典 [Chinese Loanword Dictionary] (in Chinese), 1984, page 660

## Japanese
### Etymology 1

Kanji in this term :
| 理 | 由 |
| り Grade: 2 | ゆう Grade: 3 |
| on'yomi ||

#### Pronunciation

* (Tokyo) りゆう [rìyúú] (Heiban – [0])
* IPA: [ɾʲijɯ̟ː]

#### Noun

理(り)由(ゆう) • (riyū)
* a reason
** 2016 April 23, “弱(じゃく)者(しゃ)の消(しょう)耗(もう) [Consume the Meek]”, in エルドラージ覚醒 [Eldrazi Awakening], Wizards of the Coast:
    「それはなぜ破(は)壊(かい)するのかだと？それがそうするからだ。理(り)由(ゆう)を語(かた)るなど時(じ)間(かん)と呼(こ)吸(きゅう)の無(む)駄(だ)だ。」
       “Sore wa naze hakaisuru no ka da to? Sore ga sō suru kara da. Riyū o kataru nado jikan to kokyū no muda da.”
       “Why does it destroy? It does, and to talk of reasons wastes time and breath.”
* a motive

##### See also

* 原(げん)因(いん) (gen'in, “cause”)

### Etymology 2

Kanji in this term :
| 理 | 由 |
| わけ ||
| Grade: 2 | Grade: 3 |
| jukujikun ||
For pronunciation and definitions of 理由 – see the following entry. :
| 【わけ】 | [noun] 訳, 理由: reason (for), cause Alternative spelling 訳 |
(This term, 理由, is an alternative spelling of the above term.) :

### References

* ↑ NHK Broadcasting Culture Research Institute, editor (1998), NHK日本語発音アクセント辞典 [NHK Japanese Pronunciation Accent Dictionary] (in Japanese), Tokyo: NHK Publishing, Inc., →ISBN

## Korean

Hanja in this term :
| 理 | 由 |

### Noun

理由 • (iyu) (hangeul 이유)
* hanja form of 이유 (“(South Korea) reason”)

### Noun

理由 • (riyu) (hangeul 리유)
* hanja form of 리유 (“(North Korea) reason”)

## Vietnamese

chữ Hán Nôm in this term :
| 理 | 由 |

### Noun

理由
* chữ Hán form of lí do/lý do (“reason; cause; excuse; justification”).