複雑|ふくざつfukuzatsu[0]heiban (flat)

1. na-adjective, nouncomplex; complicated; intricate; mixed (feelings)
   あれはとても複雑ふくざつな機械きかいだ。↗

   That is a very complex machine.

• Synonym煩雑はんざつWrittenWritten/formal prose. For procedures and tasks that are cumbersome and bothersome, as in 「煩雑な手続き」; stresses the bother rather than any difficulty in understanding.
• SynonymややこしいCasualColloquial. For tangled, messy situations that are a hassle, as in 「ややこしい話」; common in Kansai and carries a complaining tone.
• Synonym錯綜さくそうWrittenWritten/formal prose. For information or threads crisscrossing into a tangle, as in 「情報が錯綜する」; stresses the resulting confusion.
• Synonym込み入ったこみいったNeutralNeutral. For matters with many tangled strands, as in 「込み入った事情」 or 「込み入った話」; stresses being hard to grasp or deal with.
• Related難解なんかいWrittenWritten/formal prose. For texts and ideas that are hard to understand, as in 「難解な文章」; stresses obscurity rather than tangled circumstances.
• Related難しいむずかしいNeutralNeutral. The everyday word for hard or difficult, as in 「難しい問題」; stresses the level of difficulty, not a tangled structure.
• Related煩わしいわずらわしいCasualColloquial. For things that are annoying and a burden to deal with, as in 「煩わしい人間関係」; stresses the psychological strain rather than complexity.
• Related紛糾ふんきゅうWrittenWritten/formal prose. For discussions tangling into disorder, as in 「会議が紛糾する」; stresses quarrelling and confusion, not complexity of structure.
• Related困難こんなんNeutralNeutral. For things that are hard to carry out or overcome, as in 「困難を乗り越える」; stresses difficulty of achievement, not tangled structure.
• Related複雑化ふくざつかNeutralNeutral noun for the process of something turning complex, as in 「問題の複雑化」; points to the trend of change rather than the state itself.
• Related煩瑣はんさWrittenWritten/formal prose. For rules and details that are fiddly and cumbersome, as in 「煩瑣な規則」; even more minute and trivial than 「煩雑」.
• RelatedとらえどころのないCasualColloquial set phrase for something elusive that you cannot pin down, as in 「捉えどころのない人」; about being vague and slippery, not structurally complex.
• Antonym単純たんじゅんNeutralNeutral antonym of 「複雑」. For structures that are simple, or people who are simple-minded, as in 「単純な仕組み」.
• Antonym簡単かんたんNeutralNeutral antonym of 「複雑」. For things that are simple and easy to do, as in 「簡単な問題」; stresses ease of doing rather than structure.

Default to 「複雑」 for anything complex or tangled. For a messy hassle say 「ややこしい」; for cumbersome procedures 「煩雑」; for tangled private circumstances 「込み入った」; for obscure material 「難解」; for crisscrossing information 「錯綜」. The simple opposites are 「単純」 (simple in structure) and 「簡単」 (easy to do).

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

1. 容易よういに理解りかいや説明せつめい、処理しょり、解決かいけつができないほど、事情じじょうが絡み合からみあっている状態じょうたい。または、そのようなもの。
2. 事情じじょうが絡み合からみあっていて容易よういに理解りかいや説明せつめい、処理しょり、解決かいけつなどができないさま。
3. さまざまな心理しんりや感情かんじょうが入り混いりまじって単調たんちょうでないさま。
4. 容易よういに理解りかいや説明せつめい、処理しょり、解決かいけつができないほど、事情じじょうが絡み合からみあう。