Usage patterns 〈 事こと 〉 が 効こう を 奏そう する for an effort or measure to prove successful
The steady effort paid off, and business performance recovered.
効こう が 現あらわ れる for an effect to become apparent
It can take several weeks for the effect of the treatment to show.
効こう が 切き れる for an effect to wear off
Once the medicine's effect wore off, the fever went up again.
Expressions 効こう がある be effective; be beneficial; have an effect Kanji 効 merit, efficacy, efficiency Related words 効果 is the everyday word for 'effect' or 'result', while 効 is a more formal, literary term mostly seen in fixed expressions.
効き目 is the common, concrete word for how well a medicine or method works, whereas 効 is a terse, formal term used in set phrases like 効を奏する .
効力 emphasizes the binding or legal potency of something (like a contract), while 効 refers more generally to a beneficial result of effort or treatment.
Word family· 62 effect; effectiveness; result · effects (sound, visual, special)
valid; effective; in effect · yuko (judo)
efficiency
invalid; void; ineffective; unavailable
effect; efficacy; validity; potency
Show 21 more Show fewer immediate effect; instant effect
statute of limitations; prescription; lapse of rights after a period of time · becoming invalid or void after a set time · ageing; aging
practical effect; efficacy; effective operation
effect; efficacy; benefit
lapse; expiration; invalidation; becoming void
coming into effect; taking effect; becoming effective
use; utility; benefit; effectiveness
medical efficacy; effect of a medicine
striking effect; dramatic results; special efficacy · special effects; SFX
speedy effect; quick results; immediate action
delayed effect; delayed action
greenhouse gas
aftereffect; after effect
great effect; remarkable efficacy
efficacy; effectiveness
great efficiency; remarkable effectiveness
remarkable effect; miraculous efficacy
efficacy; effectiveness; taking effect
aftereffect
treatment efficacy; therapeutic effect
fertilizer response; effect of fertilizer
See all 62 in Explore →
Etymology The kanji 効 is composed of 交 (mix, intersect) and 力 (power), suggesting the idea of power being applied effectively. The reading こう is the on'yomi.
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