きく (聞く・効く・利く): One Sound, Several Kanji (with Examples)
One sound, several kanji
Most "one verb, many meanings" guides start from a single core image. きく is different: here you have three genuinely different verbs that share a pronunciation (a homophone set). The kana きく hides which one you mean, so Japanese leans on the kanji to keep them apart.
The good news is that the three split cleanly by what kind of thing is doing the きく:
- 聞く — you use your ears (and by extension, your questions): listen, hear, ask.
- 効く — a medicine or treatment produces a result: it takes effect, it works.
- 利く — a part or faculty does its job: the brakes work, your nose is sharp, you're considerate.
Hold onto that "ears / medicine / faculty" split and you'll almost always pick the right kanji.
One more note before the meanings: 聞く is so important that the character 聞 has its own dedicated kanji guide on Yatta!. Here we're focused on the homophone verbs — which sound goes with which kanji — so we'll keep the kanji breakdown light.
The meanings, most common first
1. To listen / to hear (聞く)
ヤッタンは部屋で音楽を聞く。
ヤッタンは へやで おんがくを きく。
Yattan listens to music in his room.
The everyday, all-purpose 聞く: taking something in through your ears, on purpose or not.
2. To ask (a question) (聞く)
モチは先生に道を聞いた。
モチは せんせいに みちを きいた。
Mochi asked the teacher the way.
聞く also means 'to ask' — 道を聞く = to ask for directions. Same kanji as 'listen.'
3. To listen attentively (聴く)
弟は目を閉じてピアノを聴く。
おとうとは めを とじて ピアノを きく。
My little brother closes his eyes and listens carefully to the piano.
聴く (above N5) is a different kanji for focused listening — music, lectures. Casual writing just uses 聞く.
4. To be effective / take effect (効く) — medicine
この薬はよく効く。
この くすりは よく きく。
This medicine works really well.
効く is for medicines, treatments, and effects producing a result. Think 効果 (kōka, 'effect').
5. To work / take effect (効く) — broader effects
冷房が効いて部屋が涼しい。
れいぼうが きいて へやが すずしい。
The air conditioning is working and the room is cool.
Anything that produces a noticeable effect can 効く — AC, seasoning, a strategy.
6. To function / work properly (利く) — a part doing its job
この車はブレーキがよく利く。
この くるまは ブレーキが よく きく。
This car's brakes work well.
利く = a mechanism or faculty performs its function. ブレーキが利く = the brakes respond.
7. To be sharp / keen (利く) — a sense or ability
ヤッタンは鼻が利くから、すぐおやつを見つける。
ヤッタンは はなが きくから、すぐ おやつを みつける。
Yattan has a keen nose, so he finds snacks right away.
鼻が利く = keen sense of smell; 気が利く = considerate/thoughtful. Set phrases with 利く.
A handy memory hook: 聞く needs ears, 効く needs medicine (or an effect), 利く needs a working part. If you can swap in "is effective," it's 効く; if you can swap in "functions / is sharp," it's 利く; otherwise it's plain 聞く.
Common collocations worth memorizing
These fixed pairings tell you instantly which きく you're dealing with:
| Collocation | Reading | Kanji | Meaning |
|---|---|---|---|
| 音楽を聞く | おんがくを きく | 聞く | to listen to music |
| 道を聞く | みちを きく | 聞く | to ask the way |
| 話を聞く | はなしを きく | 聞く | to listen to / hear a story |
| 薬が効く | くすりが きく | 効く | the medicine works |
| 効き目がある | ききめが ある | 効く | to be effective (lit. has effect) |
| ブレーキが利く | ブレーキが きく | 利く | the brakes work |
| 気が利く | きが きく | 利く | to be considerate / thoughtful |
| 鼻が利く | はなが きく | 利く | to have a keen nose |
Kanji & related verbs
Each meaning has its own character, and choosing the right one is the whole game:
- 聞く — listen, hear, ask. The default, by far the most common. Its character 聞 has a full kanji guide of its own on Yatta! if you want the stroke-by-stroke breakdown.
- 聴く (N3+) — listen attentively (music, lectures). Same reading, narrower nuance. In casual writing people often just write 聞く.
- 効く — be effective. Pairs with the noun 効果 (こうか, "effect") and 効き目 (ききめ, "efficacy").
- 利く — function / be sharp. Lives in set phrases: 気が利く, 鼻が利く, 無理が利く (to be able to push limits), わがままが利く (to be able to get away with selfishness).
When you're unsure and just writing casually, 聞く is the safe default for the "ears" meaning — but never use it for medicine or brakes.
効く vs 利く — the easy mix-up
These two are the trickiest pair, because both translate loosely as "to work." The split is what kind of thing works:
| Form | Core idea | Example |
|---|---|---|
| 効く (effect) | A medicine, treatment, or measure produces a result | 薬が効く = the medicine takes effect |
| 利く (function) | A part, sense, or faculty performs its job well | ブレーキが利く = the brakes respond / work |
A quick test: if the subject is a substance or measure that has an effect (medicine, AC, seasoning, a policy), use 効く. If the subject is a mechanism or sense that functions (brakes, nose, eyes, flexibility), use 利く. And neither of these is 聞く — that one is reserved for listening, hearing, and asking.
Quick recap
- Three verbs, one sound: 聞く (ears: listen / hear / ask), 効く (effect: medicine works), 利く (function: brakes, senses, consideration).
- All are Group 1 (う-verbs): きく → ききます, きいて, きかない — same conjugation across all three.
- 聞く also means to ask (道を聞く), not just to listen.
- 聴く (N3+) is "listen attentively"; casual writing often falls back to 聞く.
- 効く = "is effective"; 利く = "functions / is sharp." Memorize the set phrases (気が利く, 鼻が利く).
Your turn
Ready to test your N5 vocabulary in context?
Start the 5-question drill →Frequently asked questions
Is きく a ru-verb or u-verb?
All three (聞く, 効く, 利く) are Group 1 (う-verbs / godan): きく → きき-ます, きい-て, きか-ない. The conjugation is identical no matter which kanji you mean.
Does 聞く mean 'listen' or 'ask'?
Both. 音楽を聞く = to listen to music; 道を聞く = to ask the way. Context (and the particle) tells you which — but it is the same verb and the same kanji.
What is the difference between 効く and 利く?
効く is for things that produce an effect — medicine, air conditioning, seasoning (薬が効く). 利く is for parts or faculties that function — brakes, senses, flexibility (ブレーキが利く, 鼻が利く).
When do I use 聴く instead of 聞く?
聴く (N3 and above) means to listen attentively — to music or a lecture. It is the same reading, きく, but a narrower nuance. In casual writing many people just use 聞く for everything.