At the A1 level, '不可逆' (Fukagyaku) is a very difficult word that you usually won't need. However, you can think of it as a very fancy way to say 'cannot go back' or 'cannot change it back.' Imagine you drop an egg and it breaks. You cannot make it a whole egg again. That is what this word describes. In simple Japanese, we usually say 'modorenai' (cannot return). You might see this word in a science museum or a very simple book about nature. The first part 'Fu' means 'not,' the second part 'Ka' means 'can,' and 'Gyaku' means 'reverse.' So, 'not-can-reverse.' Even if you don't use it, remembering that 'Fu' means 'not' will help you with many other Japanese words later on. For now, just remember that it means something is permanent and finished.
For A2 learners, '不可逆' is a word you might encounter in news headlines or science-related materials. It is a formal word. While you would normally use 'mō modorenai' (can't go back anymore) in conversation, 'fukagyaku' is used to describe processes. For example, 'Time is irreversible' (Jikan wa fukagyaku desu). This word is made of three kanji. It's helpful to learn it as a set phrase 'fukagyaku-teki' which means 'irreversible.' You might hear it when people talk about the environment or big changes in the world. It’s like a 'one-way street' for actions or events. If you use this word correctly in a basic speech, people will think your Japanese is very advanced because it is a 'kango' (Chinese-origin word) that sounds very professional.
At the B1 level, you should begin to recognize '不可逆' in more complex contexts like news reports, documentaries, and formal articles. This word is essential for discussing topics like climate change, medical conditions, and historical events. You should understand the difference between 'fukagyaku' and 'torikaeshi no tsukanai.' While both mean 'irreversible,' 'fukagyaku' is more objective and scientific. For instance, 'irreversible brain damage' is 'fukagyaku-teki na nō-sonshō.' It describes a state that physically cannot be undone. In your own writing, you can use it to add a level of seriousness to your arguments. Instead of saying a change is 'big,' you can say it is 'irreversible' to show that the situation has fundamentally altered and cannot return to how it was before.
As a B2 learner, you are expected to use '不可逆' correctly in formal discussions and academic writing. This word is a key term in the CEFR B2 vocabulary for Japanese. You should be comfortable using its various forms: as a noun, as a na-adjective (不可逆な), and as a -teki adjective (不可逆的な). You should also be aware of its historical and political nuances, such as its use in international treaties to signify a final, unchangeable agreement. At this level, you can use it to describe abstract concepts like 'irreversible social trends' or 'irreversible economic shifts.' It is a powerful tool for expressing the finality of a process. Pay attention to its collocations with words like 'process' (katei), 'reaction' (hannō), and 'damage' (damēji). Using 'fukagyaku' instead of 'modorenai' will significantly elevate the register of your Japanese.
At the C1 level, '不可逆' should be a natural part of your high-level vocabulary. You should understand its philosophical implications, such as the 'irreversibility of time' (kako no fukagyakusei) and how this concept is used in literature and existential thought. You should also be familiar with its technical uses in fields like thermodynamics (irreversible processes), information technology (irreversible encryption), and law. C1 learners should be able to debate complex issues—like the ethics of irreversible medical procedures or the irreversible impact of AI on society—using this term with precision. You should also recognize the nuance when it is used in diplomatic contexts to indicate a 'point of no return.' Your ability to distinguish 'fukagyaku' from similar terms like 'fuhen' (immutable) or 'kōkyū-teki' (permanent) will demonstrate a deep mastery of the language.
For C2 learners, '不可逆' is a nuanced instrument used to describe the fundamental nature of reality and human systems. You should be able to analyze the rhetorical use of the word in political manifestos or scientific papers, where it is often employed to create a sense of urgency or absolute finality. Beyond its standard definitions, you should understand how the concept of 'irreversibility' plays into the Second Law of Thermodynamics and how this is metaphorically applied to social entropy. You should be able to use the word in sophisticated constructions, such as 'fukagyakusei o tamotsu' (maintaining irreversibility) or 'fukagyakuteki na tenkan-ten' (an irreversible turning point). At this level, you are not just using the word; you are handling the heavy philosophical and technical weight it carries in Japanese intellectual discourse, moving seamlessly between scientific accuracy and metaphorical depth.

不可逆 در ۳۰ ثانیه

  • Irreversible; cannot be returned to the original state.
  • Commonly used in scientific, medical, and formal political contexts.
  • Implies a permanent change or a 'point of no return'.
  • Often appears as '不可逆的な' (adjective) or '不可逆的に' (adverb).

The Japanese term 不可逆 (ふかぎゃく / Fukagyaku) is a sophisticated noun and No-adjective that translates directly to 'irreversible.' To understand its weight, one must look at its constituent kanji: 不 (Fu - Not), 可 (Ka - Possible), and 逆 (Gyaku - Reverse/Opposite). Literally, it describes a state where 'reversing is not possible.' While it originated in the rigid domains of thermodynamics and chemistry to describe reactions that cannot return to their original reactants, it has permeated modern Japanese discourse to describe life-altering decisions, environmental degradation, and historical shifts that leave no path back to the status quo.

Scientific Precision
In physics, an irreversible process is one that increases the entropy of the universe. When you fry an egg, the proteins denature in a way that they can never become a raw egg again. This is the quintessential fukagyaku phenomenon.

一度起きてしまった環境破壊は、多くの場合不可逆なプロセスである。
(Environmental destruction, once occurred, is in many cases an irreversible process.)

Beyond the lab, the word carries a somber, often philosophical tone. It is used when discussing the passage of time or the loss of a loved one. Unlike the more colloquial 'torikaeshi no tsukanai' (which implies a mistake or regret), fukagyaku is more clinical and absolute. It suggests a fundamental change in the laws of a situation. For instance, the transition from childhood to adulthood is an irreversible biological and social journey. When a diplomat speaks of an 'irreversible agreement,' they are signaling that the bridges behind them have been burned, and the only path forward is the one currently being paved.

Medical Context
Doctors use this to describe 'irreversible brain damage' (不可逆的な脳損傷). It conveys a sense of finality that helps families understand the gravity of a medical condition.

時間は常に不可逆に流れていく。
(Time always flows irreversibly.)

In the digital age, we also see this word in data management. A 'hash function' is an irreversible calculation; you can get a hash from a password, but you cannot (easily) get the password back from the hash. This technical nuance makes the word essential for IT professionals in Japan. It bridges the gap between the physical laws of the universe and the logical structures of human creation. Whether it is the melting of a glacier, the signing of a peace treaty, or the encryption of a file, fukagyaku defines the point of no return with cold, mathematical certainty.

Grammatically, 不可逆 functions primarily as a noun that often takes the particle な (na) to become an adjective, or is followed by 的 (teki) to form 不可逆的 (fukagyakuteki), meaning 'irreversibly' or 'irreversible in nature.' Mastering its usage requires understanding its collocations with words like 'henka' (change), 'katei' (process), and 'kettei' (decision).

As a Na-Adjective
When modifying a noun directly, use '不可逆な'. Example: 不可逆な反応 (An irreversible reaction).

この化学変化は不可逆なものです。
(This chemical change is something that is irreversible.)

The variant 不可逆的 is perhaps even more common in academic and formal writing. It functions as a 'no-adjective' or a 'na-adjective' depending on the sentence structure, often emphasizing the characteristic of being irreversible. For example, '不可逆的なダメージ' (irreversible damage) sounds slightly more professional than '不可逆なダメージ'. If you are writing a report on climate change or economic shifts, '不可逆的' is your best friend. It suggests that the phenomenon is not just a temporary state but a fundamental shift in the system's architecture.

The 'Point of No Return'
You can use it to describe abstract concepts like 'irreversible progress' (不可逆的な進歩) or 'irreversible loss' (不可逆的な喪失).

デジタル化の流れはもはや不可逆である。
(The trend of digitalization is already irreversible.)

When constructing sentences, pay attention to the subject. Usually, the subject is a process, a change, or a state. It is rare to see a person described as 'fukagyaku' unless you are speaking metaphorically about their growth or aging. Instead, focus on the result of an action. If you drop a glass and it shatters, the state of the glass has undergone an 'irreversible change.' If a country changes its constitution, that might be seen as an 'irreversible political shift.' By using this word, you are essentially telling your audience: 'There is no undo button here.'

You might think a word like 不可逆 is reserved for dusty textbooks, but it actually pops up in surprising places in modern Japanese life. One of the most famous (and controversial) recent uses was in the 2015 diplomatic agreement between Japan and South Korea regarding the 'comfort women' issue. The phrase used was 'saishūteki katsu fukagyakuteki ni' (finally and irreversibly). This phrasing meant that neither side could ever bring the issue up again or demand further apologies. This catapulted the word into the daily vocabulary of anyone watching the evening news, cementing its meaning as a 'permanent settlement.'

In the News
News anchors use it when discussing the 'tipping point' of climate change. Once the permafrost melts, the release of methane is often described as a 'fukagyakuteki na genshō' (irreversible phenomenon).

脳死は医学的に不可逆な状態とされている。
(Brain death is considered a medically irreversible state.)

In the business world, CEOs and tech visionaries use it to describe market disruptions. When Netflix replaced video rental stores, or when AI began to transform the workforce, these were described as irreversible shifts in the industry. If you attend a corporate strategy meeting in Tokyo, you might hear a manager say, 'This project is now at an irreversible stage,' meaning the investment has passed the point where they can pull out without total loss. It adds a sense of high stakes and professional gravity to the conversation.

Pop Culture & Philosophy
In anime or literature, a character might lament the 'irreversible nature of the past' (過去の不可逆性). It emphasizes the tragedy of not being able to fix one's mistakes.

この条約は、問題を不可逆的に解決するものだ。
(This treaty is meant to solve the problem irreversibly.)

Lastly, you will encounter it in psychology. Psychologists talk about 'irreversible developmental stages.' Once a child learns to walk or speak, they cannot 'un-learn' the fundamental neural pathways that allow for those actions. It is a word that captures the essence of growth—moving forward into a new state of being from which there is no retreat. Whether you are reading a scientific journal, listening to a political podcast, or watching a serious drama, fukagyaku is the word that signals a permanent transformation of reality.

While 不可逆 is a powerful word, it is easy to misuse if you don't understand its specific 'weight.' The most common mistake is using it for trivial situations where 'unreturnable' or 'unchangeable' would be more appropriate. For example, if you buy a shirt and can't return it to the store, you should not say the purchase is 'fukagyaku.' That is too dramatic. Instead, use 'henpin fukan' (returns not possible).

Mistake 1: Triviality
Using fukagyaku for everyday inconveniences like a missed train or a sold-out ticket. These are 'unfortunate' (zannen) or 'unchangeable' (kaerarenai), but not 'irreversible' in the grand, systemic sense.

❌ この靴の返品は不可逆です。
(Incorrect: Returning these shoes is irreversible.)
✅ この靴は返品不可能です。
(Correct: These shoes are non-returnable.)

Another common error is confusing fukagyaku with fukahi (unavoidable). While things that are irreversible are often unavoidable once they happen, they are not the same thing. 'Fukahi' refers to the inevitability of an event occurring in the future, while 'fukagyaku' refers to the impossibility of returning to a previous state after an event has occurred. If a storm is coming, it is 'fukahi.' Once the storm destroys a house, the damage is 'fukagyaku.'

Mistake 2: Confusing with 'One-time'
Sometimes learners use it to mean 'unique' or 'one-off' (ikkiri). Fukagyaku doesn't mean it only happens once; it means once it happens, the result is permanent.

不可逆なチャンス。
(Awkward: An irreversible chance.)
✅ 一度きりのチャンス。
(Natural: A once-in-a-lifetime chance.)

Finally, watch out for the kanji. The second kanji 可 (Ka) is sometimes omitted by mistake, or the third kanji 逆 (Gyaku) is swapped with 返 (Hen/Kaesu). While 'fukahen' sounds like it could mean 'unreturnable,' it's not a standard word in this context. Stick to the three-kanji compound to ensure you are understood in professional and academic settings. Remember, this word is a heavy-hitter; save it for when the consequences are truly permanent.

Because 不可逆 is so formal, you will often need more natural or emotive alternatives depending on the situation. The most common synonym in daily life is 取り返しのつかない (Torikaeshi no tsukanai). While fukagyaku is clinical and objective, torikaeshi no tsukanai is full of emotion and often implies regret or a terrible mistake.

Comparison: Objective vs. Subjective
  • 不可逆: The reaction has reached a state where the reverse path is thermodynamically impossible.
  • 取り返しのつかない: I made a huge mistake and now my life is ruined; I can't undo what I did.

彼は取り返しのつかないミスをした。
(He made an irreversible/irredeemable mistake.)

Another useful alternative is 後戻りできない (Atomodori dekinai). This literally means 'cannot go back' and is often used when someone has made a decision and must keep moving forward. It is less scientific than fukagyaku and more about the psychological state of 'no turning back.' If you are starting a new business and have spent all your savings, you are at a point of atomodori dekinai.

More Formal Alternatives
  • 恒久的 (Kōkyū-teki): Permanent / Long-lasting. Used for peace or laws.
  • 一方的 (Ippō-teki): One-way / Unilateral. Used when only one side is acting.
  • 不変 (Fuhen): Immutable / Unchanging. Used for universal truths.

この決断は後戻りできないものだ。
(This decision is one where there is no turning back.)

In summary, choose fukagyaku for science, high-level politics, and clinical descriptions. Choose torikaeshi no tsukanai for personal regrets and emotional weight. Choose atomodori dekinai for moments of determination or logistical points of no return. Understanding these shades of meaning will make your Japanese sound far more nuanced and natural to native speakers.

چقدر رسمی است؟

نکته جالب

The word gained massive public attention in Japan during the 2015 'Comfort Women Agreement' because of its heavy diplomatic weight.

راهنمای تلفظ

UK fɯkaɡʲakɯ
US fukaɡʲaku
In Japanese, this word typically follows a Heiban (flat) pitch accent pattern, though sometimes the 'ka' is slightly higher.
هم‌قافیه با
Kagyaku (Reversible) Zenyaku (Full translation) Hakyaku (Destruction) Kyakaku (Passenger) Saku (Strategy) Yaku (Role) Gaku (Learning) Raku (Comfort)
خطاهای رایج
  • Pronouncing 'gyaku' as 'jaku'.
  • Missing the 'ka' and saying 'fugyaku'.
  • Over-emphasizing the final 'u'.
  • Confusing the pitch with 'fukagyaku' (reversible - which doesn't exist as a common word without the 'fu').
  • Mixing up the kanji order.

سطح دشواری

خواندن 4/5

Requires knowledge of N2/N1 level kanji and formal vocabulary.

نوشتن 4/5

The kanji for 'Gyaku' (逆) can be tricky to write correctly.

صحبت کردن 3/5

The pronunciation is straightforward but the word is very formal.

گوش دادن 3/5

Often heard in news broadcasts or science programs.

بعداً چه یاد بگیریم؟

پیش‌نیازها

反対 (Opposite) 可能 (Possible) 変化 (Change) 戻る (Return) 不可能 (Impossible)

بعداً یاد بگیرید

恒久的 (Permanent) 暫定的 (Provisional) 収束 (Convergence) 乖離 (Divergence) 変容 (Transformation)

پیشرفته

エントロピー (Entropy) 熱力学 (Thermodynamics) 実存主義 (Existentialism) 因果関係 (Causality)

گرامر لازم

~的 (teki) suffix

不可逆的、科学的、論理的

不~ (Fu) prefix for negation

不可能、不便、不可欠

~な (na) adjective modification

不可逆な変化、綺麗な花

~かつ (katsu) for 'and also'

最終的かつ不可逆的

~の状態にある (state of...)

不可逆な状態にある

مثال‌ها بر اساس سطح

1

時間は不可逆です。

Time is irreversible.

Simple A is B structure.

2

この変化は不可逆です。

This change is irreversible.

Using 'kono' to point to a specific change.

3

不可逆なプロセスですね。

It's an irreversible process, isn't it?

Adjective + Noun structure.

4

戻ることはできません。不可逆です。

You cannot go back. It is irreversible.

Explaining a simple verb with a formal noun.

5

不可逆という言葉は難しいです。

The word 'irreversible' is difficult.

Using 'to iu' to define a word.

6

卵を焼くのは不可逆です。

Cooking an egg is irreversible.

Verb nominalization + Copula.

7

これは不可逆な反応です。

This is an irreversible reaction.

Standard 'na' adjective usage.

8

不可逆、つまり戻れません。

Irreversible, meaning you can't go back.

Using 'tsumari' for clarification.

1

自然破壊は不可逆なことが多いです。

Nature destruction is often irreversible.

Using 'koto ga ōi' to show frequency.

2

不可逆的なダメージを受けました。

It received irreversible damage.

Using the '-teki' form.

3

一度決めたら不可逆です。

Once decided, it's irreversible.

Using 'tara' for conditions.

4

この薬の効果は不可逆です。

The effect of this medicine is irreversible.

Possessive 'no' with a noun phrase.

5

老化は不可逆な現象です。

Aging is an irreversible phenomenon.

Scientific noun 'genshō'.

6

歴史の流れは不可逆的なものです。

The flow of history is something irreversible.

Using 'mono' to generalize.

7

不可逆な変化に驚きました。

I was surprised by the irreversible change.

Emotive verb 'odoroku'.

8

そのプロセスは不可逆的に進みます。

The process proceeds irreversibly.

Adverbial form 'ni'.

1

地球温暖化の影響は不可逆的な段階に達している。

The effects of global warming have reached an irreversible stage.

Using 'ni tasshite iru' (has reached).

2

この契約を解除することは不可逆的に不可能です。

Canceling this contract is irreversibly impossible.

Double negation/emphasis.

3

不可逆な脳の損傷が懸念されています。

There are concerns about irreversible brain damage.

Passive form 'ken'en sarete iru'.

4

技術の進歩は不可逆な社会の変化をもたらした。

Technological progress brought about irreversible social changes.

Using 'wo motarashita' (brought about).

5

一度失った信頼は、時に不可逆的なものとなる。

Trust once lost sometimes becomes irreversible.

Using 'toki ni' (sometimes).

6

この化学反応は不可逆であり、元の状態には戻らない。

This chemical reaction is irreversible and does not return to its original state.

Using 'de ari' for formal conjunction.

7

政治的な合意が不可逆的に成立した。

A political agreement was irreversibly established.

Formal verb 'seiritsu suru'.

8

データの削除は不可逆な操作ですので、ご注意ください。

Deleting data is an irreversible operation, so please be careful.

Polite warning 'go-chūi kudasai'.

1

熱力学第二法則によれば、エントロピーの増大は不可逆である。

According to the second law of thermodynamics, the increase of entropy is irreversible.

Using 'ni yoreba' (according to).

2

その決断が不可逆的な結果を招くことを彼は知らなかった。

He didn't know that the decision would lead to irreversible results.

Using 'wo maneku' (to lead to/invite).

3

不可逆的な環境変化を防ぐために、直ちに行動すべきだ。

In order to prevent irreversible environmental changes, we should act immediately.

Using 'beki da' (should).

4

日韓合意において「不可逆的」という言葉が重要な意味を持った。

The word 'irreversible' held significant meaning in the Japan-Korea agreement.

Using 'ni oite' (in/at).

5

不可逆的な経済のグローバル化は、多くの国に影響を与えた。

The irreversible globalization of the economy affected many countries.

Compound noun 'keizai no gurōbaruka'.

6

この疾患は進行性で、不可逆的な視力低下を引き起こす。

This disease is progressive and causes irreversible vision loss.

Using 'hikiokosu' (to cause).

7

不可逆的な決断を下す前に、もう一度検討が必要だ。

Before making an irreversible decision, another review is necessary.

Using 'kudasu' (to hand down/make a decision).

8

一度公開された情報は、インターネット上で不可逆的に拡散する。

Information once published spreads irreversibly on the internet.

Using 'kakusan suru' (to spread).

1

近代化のプロセスは、伝統的な社会構造を不可逆的に変容させた。

The process of modernization irreversibly transformed traditional social structures.

Formal verb 'henyō saseru'.

2

量子力学における観測のプロセスは、しばしば不可逆的であるとされる。

The process of observation in quantum mechanics is often considered irreversible.

Passive 'to sareru' (is considered).

3

不可逆的な時間の矢という概念は、哲学的な議論の的となってきた。

The concept of the 'irreversible arrow of time' has been a target of philosophical debate.

Idiomatic 'giron no mato' (target of debate).

4

その政策は、国内産業に不可逆的な打撃を与える恐れがある。

There is a fear that the policy might deal an irreversible blow to domestic industry.

Using 'osore ga aru' (there is a fear).

5

不可逆的な喪失感を抱えながら、彼女は生きていく決意をした。

While carrying an irreversible sense of loss, she decided to live on.

Using 'nagara' (while).

6

生態系の均衡が崩れると、不可逆的な崩壊を招く危険性がある。

If the balance of the ecosystem is disrupted, there is a risk of inviting an irreversible collapse.

Using 'kikensei ga aru' (there is a risk).

7

不可逆的なデジタル署名技術により、文書の改ざんを防止する。

Irreversible digital signature technology prevents tampering of documents.

Using 'ni yori' (by means of).

8

この和解は、両国間の問題を最終的かつ不可逆的に解決するものである。

This reconciliation is intended to solve the problems between the two countries finally and irreversibly.

Using 'katsu' (and/as well as).

1

熱力学的な不可逆性は、宇宙の終焉へと向かう必然的な流れを示唆している。

Thermodynamic irreversibility suggests an inevitable flow toward the end of the universe.

Using 'shisa shite iru' (suggesting).

2

不可逆的な構造改革は、短期的には痛みを伴うが、長期的には不可欠である。

Irreversible structural reforms involve pain in the short term but are essential in the long term.

Using 'tomonau' (to accompany/involve).

3

ポストモダンの文脈において、真理の不可逆性はしばしば疑問視される。

In the postmodern context, the irreversibility of truth is often questioned.

Using 'gimonshi sareru' (is questioned).

4

遺伝子組み換え技術の環境への放出は、不可逆的な生態学的影響を及ぼす可能性がある。

The release of GMO technology into the environment could exert irreversible ecological impacts.

Using 'oyobosu' (to exert/cause).

5

死の不可逆性を受け入れることは、人間の実存における最大の課題の一つである。

Accepting the irreversibility of death is one of the greatest challenges in human existence.

Nominalization 'koto wa' as subject.

6

不可逆的な言説の変容が、社会全体の価値観を再構築していった。

The irreversible transformation of discourse reconstructed the values of society as a whole.

Using 'saikōchiku' (reconstruction).

7

この暗号化アルゴリズムは、数学的な不可逆性に基づいている。

This encryption algorithm is based on mathematical irreversibility.

Using 'ni motozuite iru' (is based on).

8

不可逆的な決別を選んだ二人の間には、もはや言葉は必要なかった。

Between the two who chose an irreversible parting, words were no longer necessary.

Using 'mohaya' (no longer).

مترادف‌ها

取り返しのつかない 一方向の 恒久的な

متضادها

可逆 修復可能

ترکیب‌های رایج

不可逆的な変化
不可逆的な反応
不可逆的なダメージ
不可逆的なプロセス
最終的かつ不可逆的
不可逆的な決定
不可逆的な進歩
不可逆的な損失
不可逆的な段階
不可逆的な影響

عبارات رایج

不可逆性に直面する

— To face the reality that something cannot be undone.

人類は今、環境の不可逆性に直面している。

不可逆的な流れ

— An unstoppable trend or current.

グローバル化は不可逆的な流れだ。

不可逆的なポイント

— The point of no return.

不可逆的なポイントを超えてしまった。

不可逆的に解決する

— To solve something once and for all.

この問題を不可逆的に解決したい。

不可逆的な事態

— An irreversible situation (usually negative).

不可逆的な事態を招く。

不可逆的な損傷

— Irreversible damage/injury.

心に不可逆的な損傷を受ける。

不可逆な現象

— An irreversible phenomenon.

エントロピーの増大は不可逆な現象だ。

不可逆的な決断

— A decision that cannot be taken back.

不可逆的な決断を迫られる。

不可逆的な変容

— An irreversible transformation.

社会の不可逆的な変容。

不可逆な運命

— Irreversible fate.

不可逆な運命を受け入れる。

اغلب اشتباه گرفته می‌شود با

不可逆 vs 不回避 (Fukahi)

Means 'unavoidable.' Something can be unavoidable but not necessarily irreversible.

不可逆 vs 不可能 (Fukanō)

Means 'impossible.' Irreversible is a specific type of impossibility (the impossibility of returning).

不可逆 vs 不変 (Fuhen)

Means 'unchanging.' Something irreversible has changed, but it just can't change back.

اصطلاحات و عبارات

"覆水盆に返らず"

— Spilt water will not return to the tray. (Equivalent to 'no use crying over spilt milk').

覆水盆に返らず、この失敗は不可逆だ。

Proverb
"賽は投げられた"

— The die is cast. (A decision has been made and cannot be undone).

賽は投げられた。我々の計画は不可逆だ。

Literary
"後には引けない"

— Cannot pull back; committed to the course.

ここまで来たら、もう後には引けない不可逆な状況だ。

Idiomatic
"不退転の決意"

— An unshakeable, irreversible determination.

不退転の決意で、不可逆的な改革を進める。

Formal
"後の祭り"

— Too late (after the festival).

今さら後悔しても後の祭りだ。事態は不可逆だ。

Colloquial
"まな板の上の鯉"

— A carp on a cutting board (helpless and in an irreversible situation).

手術を待つ間、彼はまな板の上の鯉のような不可逆な心境だった。

Idiomatic
"背水の陣"

— Burning bridges (fighting with one's back to the river).

背水の陣で、この不可逆的な戦いに挑む。

Idiomatic
"一蓮托生"

— Sharing the same fate (irreversibly bound together).

我々は一蓮托生だ。この運命は不可逆だ。

Buddhist/Idiom
"破竹の勢い"

— An unstoppable, irreversible momentum.

彼の快進撃は破竹の勢いで、もはや不可逆だ。

Idiomatic
"一期一会"

— Once in a lifetime encounter (emphasizing the irreversibility of time).

全ての出会いは一期一会、不可逆な瞬間だ。

Cultural

به‌راحتی اشتباه گرفته می‌شود

不可逆 vs 取り返しのつかない

Both mean irreversible.

Torikaeshi is emotional/regretful; Fukagyaku is scientific/formal.

取り返しのつかないミス (A mistake I regret); 不可逆的な変化 (A scientific change).

不可逆 vs 可逆

It's the same word without 'Fu'.

Kagyaku means reversible; Fukagyaku means irreversible.

可逆反応 (Reversible reaction).

不可逆 vs 後戻りできない

Both mean no going back.

Atomodori is used for physical paths or decisions; Fukagyaku is for states of being.

後戻りできない道 (A path with no return).

不可逆 vs 恒久的

Both imply permanence.

Kōkyūteki focuses on the future lasting forever; Fukagyaku focuses on the past being unrecoverable.

恒久的な平和 (Permanent peace).

不可逆 vs 不退転

Both imply no retreat.

Futaiten is about one's determination/will; Fukagyaku is about a physical or logical state.

不退転の決意 (Unshakeable resolve).

الگوهای جمله‌سازی

B2

Aは不可逆なBだ。

老化は不可逆なプロセスだ。

B2

Aは不可逆的にBする。

環境は不可逆的に変化している。

C1

Aの不可逆性が指摘されている。

事態の不可逆性が指摘されている。

C1

Aは最終的かつ不可逆的である。

この合意は最終的かつ不可逆的である。

B2

不可逆的なダメージをAに与える。

不可逆的なダメージを脳に与える。

C2

不可逆な時間の矢に抗うことはできない。

不可逆な時間の矢に抗うことはできない。

B1

これは不可逆な反応ですか?

これは不可逆な反応ですか?

C1

不可逆的な転換点を迎える。

社会は不可逆的な転換点を迎えている。

خانواده کلمه

اسم‌ها

不可逆性 (Irreversibility)
不可逆反応 (Irreversible reaction)

فعل‌ها

不可逆化する (To make irreversible)

صفت‌ها

不可逆な (Irreversible)

مرتبط

エントロピー (Entropy)
平衡 (Equilibrium)
一方通行 (One-way)
恒久 (Permanence)
不変 (Immutable)

نحوه استفاده

frequency

Common in news, science, and formal business; rare in casual daily chat.

اشتباهات رایج
  • Using '不可逆' for a missed bus. バスに乗り遅れた。 (I missed the bus.)

    Missing a bus is temporary and trivial; 'fukagyaku' is for permanent, systemic changes.

  • Saying '不可逆の' instead of '不可逆な'. 不可逆な変化

    While 'no' is sometimes used, 'na' is the standard way to turn this noun into an adjective.

  • Confusing it with '不回避' (Unavoidable). 不可逆な結果 (Irreversible result)

    Unavoidable means it *will* happen; irreversible means it *cannot be undone* once it has happened.

  • Writing '不加逆' (using 'addition' instead of 'possible'). 不可逆

    The second kanji must be '可' (possible). Check your kanji carefully.

  • Using it for 'one-way' street directions. 一方通行 (Ippō tsūkō)

    'Fukagyaku' is abstract/scientific; 'ippō tsūkō' is for literal traffic or one-way communication.

نکات

Use with 'teki'

In most formal writing, '不可逆的' (fukagyakuteki) is more natural than just '不可逆'. It sounds more professional and descriptive.

Environmental Topics

This is a key word for discussing climate change. Use it to describe the melting of ice caps or the extinction of species.

Collocation with 'Ni'

When you want to say something 'happened irreversibly,' use '不可逆的に' (fukagyakuteki ni) before the verb.

Business Register

In business, use this to describe decisions that cannot be undone, like '不可逆的な投資' (an irreversible investment).

Kanji Breakdown

Memorize the three parts: 不 (Not), 可 (Possible), 逆 (Reverse). It literally tells you the definition.

Synonym Choice

If you are feeling sad about a mistake, use '取り返しのつかない'. If you are stating a fact, use '不可逆'.

Flat Pitch

Try to keep your voice flat when saying it. Japanese 'kango' (Chinese-origin words) often have a flatter pitch than native words.

News Keywords

When you hear 'fukagyaku' on the news, pay close attention—the speaker is talking about a very serious, permanent situation.

Essays

This word is great for the conclusion of an essay to emphasize the finality of your point.

Diplomatic Nuance

Understanding the political history of this word in Japan will help you understand why it carries so much weight in conversations about history.

حفظ کنید

روش یادسپاری

Think of 'Fu' (No), 'Ka' (Can), 'Gyaku' (Reverse). No-Can-Reverse. If you see a 'Gyakusetsu' (paradox/reverse), remember this is the 'Fu-Ka' (impossible) version of that.

تداعی تصویری

Imagine a fried egg. You can't turn it back into a raw egg. The frying process is 'Fukagyaku.'

شبکه واژگان

Time Science Death History Chemistry Entropy Physics Law

چالش

Try to identify three things in your room right now that have undergone an irreversible change (e.g., a burnt candle, a used tea bag).

ریشه کلمه

Composed of Middle Chinese-derived kanji (Kango). '不' (Not) + '可' (Possible) + '逆' (Reverse).

معنای اصلی: A technical term in logic and science meaning something that cannot be turned back.

Sino-Japanese (Kango).

بافت فرهنگی

Be careful using this in emotional arguments; it can sound cold and dismissive because it is so final.

In English, 'irreversible' is used similarly, but 'fukagyaku' in Japanese feels slightly more academic or 'stiff.'

The 2015 Japan-Korea Comfort Women Agreement (Final and Irreversible). Steins;Gate (Anime) – discussions on the irreversibility of time. Thermodynamics textbooks (The Second Law).

تمرین در زندگی واقعی

موقعیت‌های واقعی

Science Class

  • 不可逆反応
  • エントロピーの増大
  • 化学変化
  • 物理的プロセス

Hospital

  • 不可逆的な損傷
  • 脳死の判定
  • 回復不能
  • 後遺症

News/Politics

  • 最終的かつ不可逆的
  • 条約の締結
  • 歴史的転換点
  • 合意事項

Environment

  • 不可逆的な温暖化
  • 生態系の破壊
  • 気候変動
  • 絶滅

Technology

  • 不可逆圧縮
  • 暗号化
  • データ削除
  • ハッシュ関数

شروع‌کننده‌های مکالمه

"環境破壊は本当に不可逆な段階にあると思いますか? (Do you think environmental destruction is really at an irreversible stage?)"

"人生で不可逆な決断をしたことがありますか? (Have you ever made an irreversible decision in your life?)"

"時間の不可逆性についてどう考えますか? (What do you think about the irreversibility of time?)"

"デジタルの世界に不可逆なものは存在するでしょうか? (Do you think irreversible things exist in the digital world?)"

"不可逆的な変化を受け入れるのは難しいことですよね。 (Accepting irreversible change is difficult, isn't it?)"

موضوعات نگارش

今日、自分がした「不可逆な」行動について書いてみよう。 (Write about an 'irreversible' action you took today.)

もし時間を可逆にできるなら、いつに戻りたいですか? (If you could make time reversible, when would you go back to?)

社会における不可逆な進歩とは何だと思いますか? (What do you think is an irreversible progress in society?)

不可逆な喪失を乗り越える方法について自分の考えをまとめなさい。 (Summarize your thoughts on how to overcome irreversible loss.)

「不可逆」という言葉から連想するイメージを詳しく記述してください。 (Describe in detail the images you associate with the word 'irreversible'.)

سوالات متداول

10 سوال

Rarely. You wouldn't call a person 'fukagyaku.' You would say their 'actions' or 'the damage to them' is irreversible. Using it for a person sounds like they are an object or a scientific specimen.

不可能 (Fukanō) means 'impossible' in general (e.g., impossible to jump 10 meters). 不可逆 (Fukagyaku) specifically means it's impossible to *return* to a previous state after a change has happened.

Yes, but it sounds very dramatic or clinical. 'Our breakup is irreversible' (私たちの別れは不可逆だ) sounds like something out of a serious novel or a scientific analysis of a relationship.

It consists of the 'shinnyū' (road) radical on the left and the 'gyaku' (reverse) component on the right. Be careful with the stroke order of the radical!

Yes, it is '可逆' (Kagyaku). It is used in science for reversible reactions, but it is much less common in daily life than 'irreversible'.

To ensure that neither the Japanese nor the South Korean government could ever reopen the issue. It was meant to be a 'final' legal and diplomatic lock.

Yes, '不可逆圧縮' (Fukagyaku Asshuku) is the term for 'lossy compression' like JPEGs or MP3s, where data is permanently removed to save space.

It is generally considered N1 level vocabulary, but it appears in B2 level materials because of its frequency in news and science.

The opposite would be '可逆的な変化' (a reversible change) or '一時的な変化' (a temporary change).

Yes, '不可逆的な転換点' (an irreversible turning point) or '不可逆な段階' (an irreversible stage) are perfect for that.

خودت رو بسنج 190 سوال

writing

Write a sentence using 不可逆 to describe time.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Translate: 'The damage was irreversible.'

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Explain '不可逆反応' in Japanese.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Write a sentence using 不可逆的に.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Use 不可逆 to describe an egg.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Translate: 'Digitalization is an irreversible trend.'

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Discuss the 'irreversibility of death' in one sentence.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Write a warning about deleting data using 不可逆.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Is aging reversible? Answer in Japanese.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Translate: 'We made an irreversible decision.'

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Use the phrase 最終的かつ不可逆的 in a sentence.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Compare 不可逆 and 戻れない.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Write 'irreversible damage' in kanji.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Describe a broken vase using 不可逆.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Write about entropy and irreversibility.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Translate: 'Irreversible process.'

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Is history reversible? Answer in Japanese.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Use 不可逆的 in a business context.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Translate: 'Irreversibility of the past.'

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
writing

Write 'irreversible reaction' in kanji.

خوب نوشتید! تلاش خوبی بود! پاسخ نمونه را ببینید.

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Pronounce: 不可逆 (Fukagyaku)

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Time is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'This is an irreversible change.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'The damage to the brain is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'The agreement was final and irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'It's an irreversible process.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Data deletion is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'We are facing an irreversible situation.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'The irreversibility of the arrow of time.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Once you cook it, it's irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'History is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'This chemical reaction is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Irreversible environmental destruction.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'There is no turning back.' (using fukagyaku)

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Pronounce: 不可逆的な (Fukagyakuteki na)

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Digitalization is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'A final and irreversible solution.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'It flows irreversibly.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'Aging is irreversible.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
speaking

Say: 'The irreversibility of social transformation.'

این را بلند بخوانید:

درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen and identify the word: Fukagyaku.

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Kono hannō wa fukagyaku desu.' Is it reversible?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Saishūteki katsu fukagyakuteki.' How many conditions are there?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Jikan wa fukagyaku desu.' What is irreversible?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyakuteki na damēji.' What kind of damage?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyaku asshuku.' What technology is mentioned?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Entoropī no fukagyakusei.' What scientific concept?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyaku na henka.' What happened?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Mohaya fukagyaku da.' Can they return?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyaku na kettei.' Was the decision temporary?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyakuteki na tenkanten.' What point was reached?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyaku, fukagyaku.' Repeat the word.

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Nō no fukagyaku na sonshō.' Where is the damage?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Fukagyaku ni shinkō suru.' How does it progress?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:
listening

Listen: 'Kako no fukagyakusei.' What about the past?

درسته! نه دقیقاً. پاسخ صحیح:
درسته! نه دقیقاً. پاسخ صحیح:

/ 190 درست

نمره کامل!

محتوای مرتبط

واژه‌های بیشتر environment

蓄積

B1

The gradual gathering or building up of something over time, such as wealth, knowledge, or pollutants.

悪影響

B2

تأثیر یا اثر بد یا مضر بر کسی یا چیزی. معمولاً در متون رسمی یا علمی استفاده می‌شود.

生物多様性

B2

تنوع همه موجودات زنده و تعاملات آنها. 'تنوع زیستی برای سلامت اکوسیستم ضروری است.' 'ما باید از تنوع زیستی در جنگل‌ها محافظت کنیم.'

二酸化炭素

B2

دی اکسید کربن گازی بی رنگ و بی بو است که در اثر احتراق و تنفس تولید می شود.

清掃

B1

تمیز کردن اساسی، اغلب در زمینه‌های حرفه‌ای یا عمومی. معمولاً روی تابلوهایی دیده می‌شود که نشان می‌دهند مکان در حال تمیز شدن است.

気候変動

B2

Long-term shifts in temperatures and weather patterns, mainly caused by human activities like burning fossil fuels.

環境保護

B2

حفاظت از محیط زیست برای آینده ما حیاتی است.

廃棄

B1

The act of throwing something away or getting rid of it. Essential for IELTS environmental topics like waste management.

生態系

B2

اکوسیستم جامعه ای از موجودات زنده است که با محیط فیزیکی خود تعامل دارند. بوم شناسی نحوه عملکرد این سیستم ها را مطالعه می کند.

絶滅危惧種

B2

گونه‌ای از حیوانات یا گیاهان که در معرض خطر جدی انقراض هستند.

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