Translation guide
The English word "rigorous" covers several distinct meanings: strict and demanding (as in rules or training), thorough and meticulous (as in research or analysis), and harsh or severe (as in climate or conditions). Each meaning has different natural Japanese equivalents.
Describing something that is very strict, requiring great effort or precision, often in an official or formal context.
The most common and versatile word for 'strict' or 'rigorous'. Used for rules, training, discipline, and conditions.
この学校は規則が厳しい。
This school has rigorous rules.
彼は厳しいトレーニングに耐えた。
He endured rigorous training.
Emphasizes strict adherence to rules or standards, often in a formal or official sense. Slightly more formal than 厳しい.
厳格な品質管理が行われている。
Rigorous quality control is carried out.
Means 'rigorous' in the sense of being precise, exact, and leaving no room for error. Often used for methods, definitions, or procedures.
厳密な手順に従ってください。
Please follow the rigorous procedure.
Describing work or study that is done very carefully, completely, and with great attention to detail.
Means 'thorough' or 'exhaustive'. The best fit for rigorous research, investigation, or preparation.
彼らは徹底的な調査を行った。
They conducted a rigorous investigation.
徹底的な準備が必要だ。
Rigorous preparation is necessary.
Means 'meticulous' or 'detailed'. Often used for plans, analysis, or scrutiny.
綿密な分析が求められる。
Rigorous analysis is required.
Means 'elaborate' or 'intricate'. Used for very detailed and precise work, often in technical or artistic contexts.
緻密な計算に基づいている。
It is based on rigorous calculations.
Describing physical conditions that are very difficult, uncomfortable, or extreme.
Also used for harsh environments or conditions. Very common.
ここは冬の寒さが厳しい。
The winter cold here is rigorous.
厳しい自然環境で生き抜く。
Survive in a rigorous natural environment.
Means 'severe' or 'grueling'. Stronger than 厳しい, emphasizing extreme hardship.
過酷な労働条件に抗議する。
Protest against rigorous working conditions.
厳しい (kibishii) is the most general and can be used for strict people, rules, training, and harsh conditions. 厳格な (genkaku na) is more formal and emphasizes strict adherence to rules or standards, often in institutional contexts. 厳密な (genmitsu na) focuses on precision and exactness, used for methods, definitions, and procedures.
先生は厳しいが、公平だ。
The teacher is rigorous but fair.
厳格な審査基準を満たす。
Meet rigorous screening criteria.
厳密に言うと、それは正しくない。
Rigorously speaking, that is not correct.
Avoid directly translating 'rigorous' as a single Japanese word in all contexts. The appropriate term depends heavily on whether you mean strict, thorough, or harsh. Using 厳しい for a 'rigorous analysis' may sound unnatural; 徹底的な or 綿密な is better.
そのコースは徹底的な勉強を必要とする。
The course requires rigorous study.
Here 'rigorous' means thorough and demanding, so 徹底的な fits well.