Meaning
可 covers three related ideas: possibility, approval, and acceptability. Spot it in a word and you know something can be done, has been permitted, or clears the bar as passable. Think of it as a green light — a stamp that says "yes, this is okay."
The character is ancient. It depicts a bent shape paired with 口 (mouth), evoking a verbal declaration of agreement — someone opening their mouth to say "approved." Over time it came to mean anything within the realm of the doable: something that meets a minimum standard and therefore qualifies as acceptable.
Today, 可 shows up almost exclusively in compound words (熟語). You rarely hear it standing alone in conversation, but it runs through formal vocabulary — written Japanese, legal language, academic texts, and N2/N1-level grammar. It pairs with 不 (ふ) to form 不可, meaning "impossible" or "not allowed," a combination just as common as the positive side.
可 has 5 strokes and is taught in elementary school Grade 5. Its radical is 口 (mouth), echoing that original sense of spoken approval. Simple-looking but high-frequency in formal writing — essential vocabulary for N2.
Readings
On'yomi (音読み) — Chinese-derived readings
可 has one on'yomi: カ (ka). It traces back to the historical Chinese pronunciation, entering Japanese through classical texts, and is the reading you'll use in virtually every compound.
Key compounds using カ:
- 可能 (kanō) — possible, feasible. The most important word built on 可, appearing constantly in everyday and formal Japanese alike.
- 許可 (kyoka) — permission, authorization. Used when someone officially grants the right to do something.
- 認可 (ninka) — approval, certification. Common for government or institutional authorization.
- 可決 (kaketsu) — passage of a bill or motion, approval by vote. Standard in political and parliamentary contexts.
- 不可 (fuka) — impossible, not allowed, unacceptable. The negative counterpart with prefix 不.
- 可否 (kahi) — yes or no, approval or disapproval. A formal way to frame a binary choice.
Kun'yomi (訓読み) — Native Japanese readings
可 has no active everyday kun'yomi in modern Japanese. Classical and literary texts use べし (beshi) — an archaic auxiliary meaning "should" or "must" — but this belongs to classical Japanese (古文, kobun) and won't appear in modern speech. For JLPT N2, focus entirely on カ and its compounds.
Common Words & Compounds
可 generates a wide range of formal vocabulary. Here are the most useful words, grouped by theme:
Possibility & Ability
- 可能 (kanō) — possible, potential. Ex: 可能な限り = as much as possible.
- 不可能 (fukanō) — impossible. Reach for this when something simply cannot be done.
- 可能性 (kanōsei) — possibility, likelihood. Turns up constantly in news and academic writing.
- 可変 (kahen) — variable, changeable. Found in technical and scientific contexts.
- 可動 (kadō) — movable, mobile. Ex: 可動式 = mobile-type.
Permission & Approval
- 許可 (kyoka) — permission, license. Practical vocabulary you'll encounter from day one of N2 study.
- 認可 (ninka) — official authorization. Used for licenses, certifications, and government approvals.
- 可決 (kaketsu) — passage by vote, approval of a bill.
- 不可 (fuka) — not permissible, unacceptable, impossible.
- 可否 (kahi) — approval or disapproval, yes or no.
Indispensability & Physical Properties
- 不可欠 (fukaketsu) — indispensable, essential. Ex: 水は生命に不可欠だ = Water is indispensable to life.
- 可燃 (kanen) — combustible, flammable. You'll see 可燃ごみ printed on garbage bins across Japan.
- 可視 (kashi) — visible. Ex: 可視光線 = visible light spectrum.
- 可逆 (kagyaku) — reversible (chemistry and physics term).
Special Case: 可愛い
- 可愛い (kawaii) — cute, adorable. 可 hides inside this everyday word, contributing an old sense of something "deserving affection" — combined with 愛 (love) to produce the modern meaning of cute.
Example Sentences
この計画は実行可能です。
Kono keikaku wa jikkō kanō desu.
This plan is feasible to carry out.
先生から外出の許可をもらいました。
Sensei kara gaishutsu no kyoka wo moraimashita.
I got permission from my teacher to go out.
その法案は議会で可決されました。
Sono hōan wa gikai de kaketsu saremashita.
That bill was passed in parliament.
水は人間の生命に不可欠です。
Mizu wa ningen no seimei ni fukaketsu desu.
Water is indispensable to human life.
その袋は可燃ごみとして捨ててください。
Sono fukuro wa kanen gomi to shite sutete kudasai.
Please dispose of that bag as burnable trash.
彼女の猫は本当に可愛いですね。
Kanojo no neko wa hontō ni kawaii desu ne.
Her cat is really cute, isn't it!
この薬の副作用は可能性として考えておくべきです。
Kono kusuri no fukusayō wa kanōsei to shite kangaete oku beki desu.
The side effects of this medicine are worth keeping in mind as a possibility.
不可能だと思っていたことが、ついに実現しました。
Fukanō da to omotteita koto ga, tsui ni jitsugen shimashita.
Something I thought was impossible finally came true.
この工事には市の認可が必要です。
Kono kōji ni wa shi no ninka ga hitsuyō desu.
This construction requires city authorization.
Memory Tip
Picture 可 as a bent arm (丁) over an open mouth (口) — someone raising a hand and calling out "Approved!" The hand goes up, the mouth confirms it. Whenever you spot 可, that image signals: this is allowed, this is possible.
Bonus: the reading カ (ka) sounds like the English word "can" — and 可能 (kanō) means exactly that: can do, possible. Let that sound hook anchor the reading.