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無効

mukō
adjectivenoun★Intermediate— invalid
⚖️Law
formal

Invalid, void, or ineffective (legally or functionally)

無効なパスポートは国外旅行に使えません

An invalid passport cannot be used for international travel.

💡

Commonly used in legal contexts to describe something that lacks legal force or effect.

general

Not working or ineffective

このコードは無効です

This code is invalid.

Collocations

無効にするto invalidate無効なinvalid

Synonyms

無効な効力がない無価値な

Antonyms

有効有効な効力がある

Related Phrases

無効にするphrase
to invalidate
無効なパスポートphrase
invalid passport

💡Pro Tip

Legal vs. General Use

In legal contexts, 無効 refers to something that is legally void, while in general contexts, it can mean something that is not working or effective.

⚡Gold Rule

Legal Context

In legal documents, 無効 is often used to describe contracts or actions that are legally invalid.

📖Word Origin

Composed of 無 (mu, 'not') and 効 (kō, 'effect'), literally meaning 'without effect'.

📝Usage Notes

In legal contexts, 無効 is often used to describe contracts, documents, or actions that are legally void. In everyday language, it can describe anything that is not functional or effective.

Word Breakdown

無
not
prefix
+
効
effect
root
和英辞典

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