Negative Prefixes: 未, 無, 非, 否, & 不
Prefixes are cumbersome in Japanese as they are in English. English has the negative prefixes un-, non-, a-, in-, de-, etc., while Japanese similarly has the negative prefixes 未～, 無～, 非～, 否～, and 不～.
Although there are no rules that determine which of these prefixes are to be used, corresponding these endings with the following Japanese and English keywords will help you tremendously in understanding how they are used.
| 未～ | まだ…ない | Incompletion |
| 無～ | ない・存在しない | Absence |
| 非～ | しない・ではない | Unjustifiability |
| 否～ | 同意しない | Noncompliance |
| 不～ | ではない | Simple Negation |
Another thing to keep in mind about these prefixes is that although they are being referred to as prefixes, it is not a 100% guarantee that what they attach to can be used in isolation as independent words. This is because they are being viewed as prefixes based on how they are used from a Chinese language perspective. For instance, anxiety in Japanese is 不安. 安, however, is not used as the antonym of 不安. Instead, the antonym of 不安 is 安心. These are simply quirks that you will need to become accustomed to as you learn words with these prefixes.
未～: Incompletion
Simply put, this prefix indicates incompletion. Meaning, something isn’t quite so yet, but it will (most likely) be so in the future.
1. 未熟なだけに、かえって被害を起こす可能性が高いのです。
Precisely because (X) is inexperienced, the possibility of him causing damage is all the more high.
2. きのう、未公開の映画を観ました。
I watched an unreleased movie yesterday.
3. 未解決の事件を纏めました。
I have compiled unresolved cases.
4. 息子が未成年飲酒をしたということで警察に連れていかれました。
My son was taken by police for underage drinking.
5. もしも未亡人になったら、暮らし方は今までと違うのか。
If you were to become a widow, how would the way you live differ from what it is now?
6. 未経験者ばかりのオフィスで働いています。
I work at an office full of inexperienced people.
7. 人間は誰もが未完成だ。
Any and all people are incomplete.
8. もしかしたら未確認飛行物体を見たかもしれない。
I may have possibly seen an unidentified flying object.
9. 体験版を通じて、たくさんの未発表のポケモンがリークされてしまった。
Many unrevealed Pokémon were accidentally leaked through the demo version.
10. 未開発市場に乗り出す。
To set out in undeveloped markets.
11. 10歳未満の子供を対象としています。
We are targeting children under ten.
12. わたしは未婚ですが、子供が欲しいです。
I’m unmarried, but I want a child.
無～: Absence
無～ attaches to things that are nouns (in Chinese and as an effect can be viewed as nouns in Japanese). It may result in an adjective or adverb on a case-by-case basis, though. This prefix indicates total lack. It typically only attaches to Sino-Japanese words. When dealing with non-Sino-Japanese words, ～なし is preferred (ex. 底なし = bottomless).
13. 無人島に住みたいと思っています。
I want to live on an uninhabited island.
14. 会員登録は無料ですか。
Is membership registration free?
15. 一人で泣いたって無意味だよ。
It’s meaningless to cry by yourself.
16. 可能性は皆無に等しい。
The likelihood (of it) is essentially nonexistent.
17. 夜中に無数の星々を眺める。
To gaze at the endless stars in the middle of the night.
18. 無論、その通りです。
Of course, that’s exactly the case.
19. 無視されたくないです。
I don’t like being ignored.
20. ジンバブエは無法地帯のソマリアよりも治安が悪いと聞いています。
I’ve been hearing that public order in Zimbabwe is worse than Somalia which is lawless.
21. 無職の男性が逮捕されました。
An unemployed male was arrested.
22. 彼女は無表情な顔をして黙っていた。
Her face was expressionless as she stayed quiet.
23. 無意識に歯を食いしばる癖を治したい。
I want to fix my habit of unconsciously grinding my teeth.
24. 無関心な相手に対しては怒りを感じません。
I don’t feel anger towards those who are uninterested.
Although not an example of the prefix, you will also see the character 無 found in the 熟字訓 reading of the native word for “fig,” which is イチジク. This is because figs, despite having many stamen and pistils, they are not visible from the outside, thus the spelling 無花果.
非～: Unjustifiability
The prefix 非～ indicates that something is not belonging to a certain state of being. It is used to show unjustifiability. Meaning, whatever it is referring to, there is a state in which it ought to be but this is the negation of it being so. More emotion, as an effect, can be seen in many examples of it.
i. 不合理: Simple negation of something being rational.
ii. 非合理: Emotional appeal to something being irrational/illogical.
非～ usually attaches to nouns but may result in adjectives depending on the phrase. It can attach to Sino-Japanese, native, and foreign words.
25. 非常識な妻に息子を育てさせるのは絶対に嫌です。
I absolutely don’t want to let my senseless wife raise our son.
26. 非割り込み型優先度順サービス
Non-preemptive priority service
27. 非アフリカ系の現代人が、DNAの1～4%をネアンデルタール人から受け継いでいる。
Non-African descent modern humans inherit 1~4% of their DNA from Neanderthals.
28. 現実の世界から非現実の世界に入っていってしまう。
To end up entering an unreal world from the real world.
29. 非科学的な発言が大嫌いだ。
I hate nonscientific remarks.
30. このページは非表示になっています。
This page does not display.
31. これからは非婚の男性が増えるでしょう。
Men who aren’t married (and don’t wish to) will increase from now on.
32. 平日は非常勤職員として働いています。
On week days I work as a part-time worker.
33. 常温で固体の非金属元素といえば、ケイ素などあります。
In speaking of non-metal elements that are solid at room temperature, there is silicon.
否～: Noncompliance
The prefix 否～ is not nearly as common as any of the previous ones, but when it is used, it indicates a meaning of noncompliance.
34. その事実を否定することはできないし、否定しても意味がない。
You can’t even deny the truth, and even if you were to, there would be no point.
35. 議会に否決されたらどうなるのか。
What happens if it’s rejected by the assembly?
36. 被告は容疑を否認しています。
The defendant is denying the allegation.
不～: Simple Negation
The prefix 不～ attaches to adjectives and verbs to show simple negation. It may not be absolute negation, though. For instance, it may indicate stagnation in some sense. 不～ typically follows nouns to negate an action, and it typically follows 形容動詞 to negate a state.
37. 人は、気分がいいときは健康な食べ物を、ストレスを感じているときは不健康な食べ物を選ぶ傾向がある。
People have the tendency of choosing healthy foods when they feel good and unhealthy foods when they’re under stress.
38. 先程お送りしたメールに不備がありました。
There was a fault in the e-mail that I had just sent you.
39. 悪妻は百年の不作。
A bad wife leads to 100 years of failure.
40. 今年は不況のため採用を控えます。
We are holding off on hiring this year due to recession.
41. 老眼は不便だね。
Farsightedness due to old age is inconvenient, you know.
42. 海外で行方不明になる。
To go missing overseas.
不～ ＋Native Words
不～ has been around long enough to follow a select number of native words.
43. 不行き届きの点は許してください。
Please forgive the carelessness.
44. 手打ちで不揃いの麺が多い。
There are many uneven noodles made by hand.
45. なぜ不真面目な人ほど、出世するのか。
Why is it that the less serious someone is the more he advances in life?
不・無（ぶ）～: Ill-representation
This is yet another prefix which can be written as either 不～ or 無～ with no true rules as to when you should use which aside from standard convention on a case-by-case basis. Most examples of this involve 形容動詞 as equivalents of the English prefixes “mis-“ and “ill-.”
46. 手先が不器用すぎる。
I’m too clumsy with my hands.
47. 無愛想な顔をしていると、相手も無愛想になる。
Whenever you have a blunt look on your face, your opponent will also become blunt.
48. 顔が不細工な人と付き合えますか。
Are you capable of dating someone with an ugly face?