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無効

mukō
noun★中級— 無効な (Invalid, Null and Void)
正式的

法的効力がなく、有効ではない状態

彼の運転免許は無効になった。

His driver's license became invalid.

💡

法的文脈でよく使用される

類義語

無効化効力なし

反義語

有効効力あり

💡プロのヒント

使用例

無効は、法律や規則の効力を失ったことを示す

📖語源

無（ない）+ 効果（効）

📝使用上の注意

主に法的または技術的な文脈で使用

単語の分解

無
ない
prefix
+
効
効果
root
国語辞典

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