利かす・効かす|きかすkikasu[0]heiban (flat)
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Which spelling to use
利かす利かす is the more common written form of this verb. It is used for meanings such as bringing out an effect, putting something to good use, or using threats or intimidation.
効かす効かす is less common than 利かす, but it is the recommended form for beginners; it carries the same meanings, including bringing out an effect and making use of threats or intimidation.
Definitions
- godan verb, transitive verbto bring out (the effect of); to put to good use; to make use of (e.g. threats); to use (e.g. intimidation); to take advantage of (e.g. one's influence); to season (with salt, etc.); to put in
- godan verb, transitive verbto use (tact, wit, etc.); to exercise; to display
Conjugation
| Dictionary form | 利かす（きかす） |
|---|---|
| Polite (masu) | 利かします（きかします） |
| Negative (nai) | 利かさない（きかさない） |
| polite (masen) | 利かしません（きかしません） |
| classical zu / nu | 利かさず・利かさぬ（きかさず・きかさぬ） |
| Past (ta) | 利かした（きかした） |
| polite (mashita) | 利かしました（きかしました） |
| Past negative (nakatta) | 利かさなかった（きかさなかった） |
| polite (masen deshita) | 利かしませんでした（きかしませんでした） |
| Te form | 利かして（きかして） |
| Potential | 利かせる（きかせる） |
| Passive | 利かされる（きかされる） |
| Causative | 利かさせる（きかさせる） |
| Causative passive | 利かさせられる（きかさせられる） |
| Conditional (ba) | 利かせば（きかせば） |
| tara | 利かしたら（きかしたら） |
| Volitional | 利かそう（きかそう） |
| polite (mashou) | 利かしましょう（きかしましょう） |
| Imperative | 利かせ（きかせ） |
Common forms generated by rule; see the senses for honorific or irregular usage.
Transitive / intransitive pair
薬が効く
薬を効かす
効く (intransitive) describes something taking effect on its own, as in 薬が効く 'the medicine works.' 利かす (transitive) describes deliberately making something take effect, as in 薬を効かす 'to make the medicine work.'
Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only
Synonyms & antonyms
- Synonym使うつかうNeutralThe everyday, most common word for using something: you take a tool or method and put it to work. It lacks 「利かす」's nuance of bringing out an effect or seasoning food.
- Synonym利用りようNeutralTo use something to your own advantage, making good use of it for benefit, as in 「制度を利用する」.
- Synonym活用かつようNeutralMaking full, effective use of something's abilities or functions; it also means grammatical conjugation.
- Synonym働かせるはたらかせるNeutralTo put someone to work, or to exert an ability, especially the brain or imagination, as in 「頭を働かせる」.
- Synonym用いるもちいるWrittenA written, formal word for adopting and using a method or employing a person.
- Synonym役立てるやくだてるNeutralTo turn something to account, putting it to a useful purpose, as in 「経験を役立てる」.
- Related使用しようWrittenA written, formal word for use, centering on using objects and facilities, as in 「使用禁止」.
- Related運用うんようWrittenA written, formal word for putting funds, systems, or institutions into operation, as in 「資金運用」.
- Antonym殺すころすNeutralTo suppress or kill off something so it has no effect, as in 「味を殺す」; the direct opposite of 「利かす」.
- Antonym無効にするむこうにするWrittenA written, formal phrase for making something invalid or disabling it — the opposite of 「利かす」 bringing an effect out.
Use 「利かす」 for bringing out wit, effect, or seasoning, often as 「気を利かす」「機転を利かす」「塩を利かす」「睨みを利かす」. For ordinary use of a tool or method pick 「使う」; for making full, effective use of something pick 「活用」.
Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only
Japanese definitions
Kanji in this word
