Explore 効 in words about effects, validity and efficiency. Learn each reading in a complete word.

The idea

効 has 8 strokes; follow the linked diagram. 効く（きく） means to work or take effect; 効果（こうか） is an effect, 有効（ゆうこう） means valid or effective, and 効率（こうりつ） means efficiency.

Patterns to compare
WordReading
効くきく
効果こうか
有効ゆうこう
効率こうりつ

Examples

  • この薬くすりは頭痛ずつうによく効ききます。This medicine works well for a headache.
  • 新あたらしい方法ほうほうの効果こうかを確たしかめました。We checked the effect of the new method.
  • この切符きっぷは明日あしたまで有効ゆうこうです。This ticket is valid until tomorrow.
  • 仕事しごとの効率こうりつを上あげました。We improved work efficiency.
  • この部屋へやは冷房れいぼうがよく効きいています。The air conditioning is working well in this room.
  • 定期的ていきてきな運動うんどうは健康けんこうの維持いじに効果的こうかてきです。Regular exercise is effective for maintaining health.

Read-aloud uses a synthetic Japanese voice available on your device. Voice quality and availability vary; it does not assess your pronunciation.

Watch out

効果 is the result of an action; 効率 concerns the resources used to achieve a result. 効く can also describe air conditioning working well.

Try it yourself

  1. Write the reading of 効く in hiragana.

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    きく

    効く is きく: the medicine works. Learn the verb with its okurigana く.

  2. Write the reading of 効果 in hiragana.

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    こうか

    効果 is こうか: it means an effect. Both characters form one noun.

  3. Choose the missing kanji: 有＿（ゆうこう）［効／交］.

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    効

    効 completes 有効（ゆうこう）, meaning valid or effective; a ticket can be 有効.

Use it today

Write 効 using the diagram. Cover the table, read 効く and 効果, and make a sentence with one of them.