周到|しゅうとうshuutou[0]heiban (flat)

1. na-adjective, nouncareful; thorough; meticulous; scrupulous
   その理論りろんは周到しゅうとうな研究けんきゅうに基もとづいている。↗

   The theory is based on thorough research.

• Synonym綿密めんみつWrittenFor close-knit, rigorous plans and investigations, as in 「綿密な計画」; a written/formal word. 周到 stresses preparation that leaves nothing out.
• Synonym入念にゅうねんNeutralCareful, elaborate work that stresses the effort invested, as in 「入念な準備」; it centers on the doing itself, not on all-around consideration.
• Synonym念入りねんいりNeutralThorough and conscientious, with care given fully in the process, as in 「念入りに洗う」 or 「念入りな化粧」; the focus is on how carefully something is done.
• Synonym細心さいしんNeutralMeticulous attention to detail, a matter of mindset, as in the set phrase 「細心の注意」; it points to careful watchfulness rather than thorough preparation.
• Synonym注意深いちゅういぶかいNeutralAn adjective for careful, watchful attention, stressing observation, as in 「注意深く見る」; it is about vigilance, not all-around preparation.
• Related丁寧ていねいNeutralA wide-ranging word covering both politeness and careful work; it stresses a courteous attitude or meticulous manner rather than all-around preparation.
• Related丹念たんねんNeutralPainstaking, unhurried work; it stresses patience and time spent, as in 「丹念に調べる」, rather than completeness of preparation.
• Related完璧かんぺきNeutralFlawless or perfect, stressing that the result has no defects at all; it does not specifically point to thorough preparation the way 周到 does.
• Related慎重しんちょうNeutralCautious and prudent, stressing that one avoids rash action; thorough preparation is not implied, so it does not always replace 周到.
• Related完全かんぜんNeutralComplete, with nothing missing; it describes a state rather than the process of preparing, so it differs from 周到's focus on preparation.
• Related丁重ていちょうWrittenA written/formal word for courteous, respectful treatment; it stresses full courtesy, as in 「丁重に断る」, not thoroughness of preparation.
• Related徹底的てっていてきNeutralExhaustive, carrying something through to the end with nothing left over, as in 「徹底的に調べる」; the emphasis is on thoroughness of execution.
• RelatedパーフェクトCasualA colloquial loanword for perfect, judging results as full marks; it also means a perfect game, and is not about careful preparation.
• Relatedきめ細かきめこまかNeutralAttentive down to the smallest detail, often of considerate treatment, as in 「きめ細かなサービス」; it highlights care for details, not preparation.
• Related精到せいとうWrittenA rare written/formal word meaning detailed and well-considered; it describes analyses, accounts and the like rather than preparation.
• Antonym粗雑そざつNeutralThe direct opposite of considerate, thorough 周到: rough, slapdash work done without care for details.
• Antonymいい加減いいかげんCasualA colloquial antonym: halfhearted, perfunctory and irresponsible, the opposite of 周到's all-covering care.

Use 「周到」 for preparation and consideration that covers everything, as in 「用意周到」 or 「周到な準備」. For tight, rigorous plans say 「綿密」; for doing something with care and effort, 「入念」 or 「念入り」; for fine attention, 「細心」; for attentive service, 「きめ細か」. The antonyms are 「粗雑」 and 「いい加減」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 準備じゅんびや注意ちゅういが行き届いきとどいて手落ておちのないさま。