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理由 (りゆう) Japanese meaning | Kotomora

理り由ゆう

also: わけ

り

ゆ

う

Common wordJLPTN4Freq.FrequencyTop 500

Meanings

1

noun

reason; grounds; motive

General term for the cause, basis, or justification for an action, decision, or situation. Can also imply a pretext or excuse depending on context.

遅ち刻こくの理り由ゆうを説せつ明めいしてください。
Please explain the reason for your lateness.
彼かれが辞

や

め

た

理り

由ゆう

は

何なん

です

か

。

What is the reason he quit?

Written forms

理由Usage100%
- りゆう
  Standard kanji spelling; the most common written form.
- わけ
  gikun (meaning-based reading) or jukujikun
わけ
gikun (meaning-based reading) or jukujikun
Gikun/jukujikun reading; rarely used in modern writing. The word わけ is normally written in kana.

Kanji

理logic, arrangement, reason
由wherefore, a reason

Similar words

原げん因いん
原因 refers to a direct cause, often in a causal chain (e.g., cause of an accident). 理由 is broader, covering motives, justifications, and grounds, not necessarily a direct cause.
わけ
わけ is a more colloquial and explanatory term, often used in phrases like 〜わけだ (that's why...). 理由 is more formal and concrete.

Etymology

Compound of 理 (logic, principle) and 由 (origin, cause). The reading りゆう is the standard on'yomi. The rare reading わけ is a jukujikun, assigning the native Japanese word わけ to the kanji compound.