Translation guide
The English word 'thorough' describes something done completely, with great attention to detail, or covering all aspects. In Japanese, there is no single direct equivalent; instead, various adjectives, verbs, and adverbs are used depending on whether you mean 'complete', 'detailed', 'meticulous', or 'exhaustive'.
Describing an action, investigation, or knowledge that is comprehensive and leaves nothing out.
A na-adjective meaning 'thorough' or 'exhaustive'. Often used for investigations, cleaning, or reforms.
彼はその問題を徹底的に調査した。
He conducted a thorough investigation of the issue.
A na-adjective meaning 'sufficient' or 'thorough' in the sense of being enough. Often used for preparation or explanation.
十分な準備が必要だ。
Thorough preparation is necessary.
A na-adjective meaning 'meticulous' or 'detailed'. Used for plans, investigations, or analysis.
綿密な計画を立てた。
We made a thorough plan.
A na-adjective meaning 'scrupulous' or 'thorough'. Often used for careful preparation or consideration.
周到な注意を払った。
We paid thorough attention.
Emphasizing carefulness and attention to detail in work or examination.
An i-adjective meaning 'detailed' or 'meticulous'. Commonly used for instructions, work, or observations.
彼は細かいところまで気がつく。
He is thorough and notices even the small details.
A na-adjective meaning 'painstaking' or 'thorough'. Often used for careful work or research.
A na-adjective meaning 'careful' or 'thorough'. Used for preparations or checks.
Expressing that an action is done completely or to the fullest extent.
An adverb meaning 'completely' or 'thoroughly'. Often used for changes of state or completion.
彼のことはすっかり忘れていた。
I had thoroughly forgotten about him.
Adverbial form of 徹底的, meaning 'thoroughly' or 'exhaustively'.
部屋を徹底的に掃除した。
I cleaned the room thoroughly.
A colloquial adverb meaning 'thoroughly' or 'to the end'. Used in casual speech.
Describing someone who knows a subject completely or has deep understanding.
A verb phrase meaning 'to be thoroughly familiar with' or 'to be well-versed in'.
彼は日本の歴史に精通している。
He has a thorough knowledge of Japanese history.
An i-adjective meaning 'detailed' or 'knowledgeable'. Commonly used for people who know a lot about something.
彼はコンピューターに詳しい。
He has a thorough knowledge of computers.
There is no single Japanese word that covers all uses of 'thorough'. Translating directly as 'thorough' in every context will sound unnatural. Choose the word that matches the specific nuance: completeness, detail, or intensity.
彼女は徹底的に説明した。
She gave a thorough explanation.
その政策の徹底的な見直しが必要だ。
We need a thorough review of the policy.
丹念な調査が行われた。
A thorough investigation was carried out.
入念なチェックが必要だ。
A thorough check is necessary.
とことん話し合おう。
Let's discuss it thoroughly.