原因

gen'in
nounIntermediate💡 cause
formal

The root or basis for something that happens; the factor that makes something happen.

病気の原因を突き止める。

Find out the cause of the illness.

地震の原因はプレートの移動だ。

The cause of the earthquake is the movement of tectonic plates.

💡

Used for both concrete and abstract causes. Often followed by particles like の or を.

Collocations

原因を追究するto investigate the cause原因不明unknown cause主な原因main cause

Antonyms

💡Pro Tip

Distinguishing 原因 vs. 理由

原因 refers to the objective cause of an event, while 理由 refers to the subjective reason behind an action or decision. For example, 'The cause of the fire was a gas leak' (原因) vs. 'He left early for personal reasons' (理由).

Gold Rule

Causality in Japanese

原因 is used when discussing causality in a logical or scientific sense. It often appears in phrases like '原因を特定する' (identify the cause) or '原因を究明する' (investigate the cause).

📖Word Origin

From Middle Chinese 原因 (yúan yīn, 'original cause'). The kanji 原 means 'original' or 'source' and 因 means 'cause' or 'depend on'.

📝Usage Notes

原因 is more formal than 理由 (reason) and implies a direct, often scientific or logical cause. It is commonly used in academic, technical, or analytical contexts.

Word Breakdown

original, source, root
root
+
cause, depend on
root
和英辞典