Translation guide
The English word "illegal" refers to actions that are against the law. In Japanese, the most common equivalent is 違法 (ihō), but depending on context, other words like 不法 (fuhō) or 非合法 (higōhō) may be used. This guide helps learners choose the right expression.
Describing an action, activity, or thing that is prohibited by law.
The most common and general term for 'illegal'. Used in legal contexts and everyday speech.
違法行為は罰せられます。
Illegal acts will be punished.
それは違法ですか？
Is that illegal?
Often used in compounds like 不法侵入 (trespassing) or 不法滞在 (illegal stay). Slightly more formal or legalistic than 違法.
不法侵入で逮捕された。
He was arrested for illegal entry.
Means 'illegal' but often implies something done secretly or outside the law, like underground activities. Less common in daily speech.
非合法な組織が関与している。
An illegal organization is involved.
Referring to drugs that are prohibited by law.
Standard term for illegal drugs.
違法薬物の使用は犯罪です。
Using illegal drugs is a crime.
Specifically refers to stimulants (often methamphetamine), which are illegal in Japan. Commonly used in news.
彼は覚醒剤所持で捕まった。
He was caught for possession of illegal stimulants.
Parking or driving in a way that breaks traffic laws.
The standard term for illegal parking.
ここは違法駐車が多い。
There is a lot of illegal parking here.
A specific criminal act.
A person who stays or works in a country without legal permission.
Standard term for an illegal overstayer or undocumented immigrant.
不法滞在者が増えている。
The number of illegal immigrants is increasing.
Refers to illegal employment or working without proper visa.
不法就労は法律で禁止されている。
Illegal employment is prohibited by law.
違法 (ihō) is the most general and common. 不法 (fuhō) often appears in legal compounds (不法行為, 不法侵入). 非合法 (higōhō) implies clandestine or underground activities, and is less common in everyday speech.
In many cases, 'illegal' is not directly translated. For example, 'illegal copy' is often 海賊版 (pirated edition) rather than 違法コピー. Use natural Japanese expressions.