結構|けっこうkekkou[1]atamadaka (head-high)

1. na-adjectivesplendid; nice; wonderful; delightful; lovely; excellent; fine
   好奇心こうきしんがお旺盛おうせいなのは大変たいへんに結構けっこうなことである。↗

   A healthy curiosity is truly a fine thing.
2. na-adjectivesufficient; satisfactory; enough; fine; all right; OK
   どちらの日ひでも結構けっこうです。↗

   Either day is OK.
3. na-adjectivenot needing (any more of something); (already) having enough; fine (as in "I'm fine"); no, thank you
   いや結構けっこうです。たくさんいただきました。↗

   No more, thank you. I'm full.
4. adverbrather; quite; fairly; pretty; surprisingly; quite a bit; fairly well
   彼女かのじょの髪の毛かみのけは結構けっこう短みじかい。↗

   The woman's hair is quite short.
5. nounstructure; construction; framework; architecture

• Synonym良いよいNeutralThe general word for good. 「結構」 also covers good and enough, but leans toward polite approval or polite refusal.
• SynonymよろしいFormalA formal variant of 「よい」, mostly for permission or asking, as in 「よろしいですか」; for declining, 「結構です」 is the usual choice.
• Synonym良好りょうこうWrittenWritten style for objective assessments of condition or results, as in 「経過良好」.
• Synonym好ましいこのましいWrittenMeans appealing or desirable, with a judging tone; leans toward written prose.
• SynonymいいCasualThe colloquial 'good'; also used to decline, as in 「もういいです」, more casual than 「結構です」.
• Synonym満足まんぞくNeutralMeans satisfied or sufficient, as in 「満足する」, stressing the feeling of contentment.
• SynonymかなりNeutralAdverb meaning fairly or quite, as in 「かなり難しい」; close to adverbial 「結構」, with strength depending on context and tone.
• SynonymなかなかNeutralMeans quite or considerably, often with admiring surprise; with a negative it means not easily, as in 「なかなか来ない」.
• RelatedずいぶんNeutralAdverb meaning quite or very, often with a sense of surprise, as in 「随分寒い」; adverbial 「結構」 is milder.
• Related十分じゅうぶんNeutralMeans enough or sufficient, as in 「これで十分」, focusing on quantity; 「結構」 also covers good.
• Related誠にまことにFormalAdverb meaning truly or very, used in formal thanks and apologies in both speech and writing, as in 「誠にありがとうございます」.
• Related無難ぶなんNeutralMeans safe, free of mistakes, as in 「無難な選択」; a modest verdict that something is unobjectionable, without the warmer approval 「結構」 can carry.
• Related大変たいへんNeutralAdverb meaning very, stronger than 「結構」, as in 「大変お世話になりました」; also means serious.
• Related適切てきせつWrittenMeans apt or fitting, as in 「適切な対応」, stressing suitability to the situation; written flavor.
• Related大丈夫だいじょうぶCasualMeans all right or no problem; also declines things, as in 「大丈夫です」, more easygoing than 「結構です」.
• Related適当てきとうNeutralMeans suitable, but also careless or half-hearted, as in 「適当に答える」 — a sense 「結構」 lacks.
• Related相応そうおうWrittenMeans befitting one's status or ability, as in 「年相応」, stressing proportion; written style.
• Related妥当だとうWrittenMeans valid or reasonable, as in 「妥当な判断」, stressing soundness of judgment; written style.
• RelatedまずまずCasualMeans passable or so-so, as in 「まずまずの出来」; a lower rating than 「結構」.
• Antonym粗末そまつNeutralOpposite of the 'splendid' sense of 「結構」: crude or shabby, or treating things carelessly.
• Antonym不十分ふじゅうぶんNeutralOpposite of the 'enough' sense of 「結構」: insufficient or falling short.
• Antonym不完全ふかんぜんWrittenOpposite of the 'complete' sense of 「結構」: incomplete or flawed; written style.

Use 「結構」 for 'that's fine,' 'that's enough,' or a polite 'no, thank you.' For formal permission use 「よろしい」; for casual refusals 「いい」 or 「大丈夫」. For 'quite, fairly' use 「かなり」 or 「なかなか」; for sheer sufficiency, 「十分」.

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

1. 完成かんせいしており不足ふそくがないものや状態じょうたい。よろしいこと。
2. かまわないこと。支障ししょうなく受け入うけいれられること。
3. （足たりているので）不要ふようであること。いらないこと。
4. 並なみでなく、かなり。
5. （構造物こうぞうぶつの）構成こうせい、構造こうぞう
6. 計画けいかく、（作品さくひんの）筋書すじがき
7. 構造物こうぞうぶつなどを組み立くみたてること。構成こうせい。