容易|よういyoui[0]heiban (flat)

1. na-adjective, nouneasy; simple; plain
   ココの知能指数ちのうしすうを調しらべるのは容易よういではない。↗

   Testing Koko's IQ is not easy.

• SynonymやさしいNeutralCommon in speech, mostly for problems or content that isn't hard, as in 「易しい問題」. 「容易」 leans written and stresses doing something without effort.
• SynonymやすいNeutralMostly used as a suffix, as in 「分かりやすい」「壊れやすい」; on its own meaning easy it now sounds dated.
• Synonym簡単かんたんNeutralThe everyday go-to; also covers simple structure or brevity. 「容易」 leans written and centers on something being not hard to do.
• Synonym簡易かんいNeutralFor simplified, bare-bones facilities or procedures, as in 「簡易トイレ」. 「容易」 just means not difficult.
• Synonym平易へいいWrittenWritten/formal prose, typically for writing or explanations that are easy to follow, as in 「平易な言葉」.
• Synonym生易しいなまやさしいNeutralUsually with a negative, as in 「生易しいものではない」, stressing that something is by no means simple.
• SynonymたやすいNeutralDoing something with ease, as in 「たやすく解ける」; a touch more colloquial than 「容易」.
• Synonym安易あんいNeutralOften pejorative: taking the easy way out, simplistic, as in 「安易な考え」. 「容易」 is neutral.
• Synonym手軽てがるNeutralHandy and fuss-free, as in 「手軽な料理」. 「容易」 centers on low difficulty.
• Synonym楽らくNeutralComfortable and effortless, as in 「楽な仕事」. 「容易」 centers on low difficulty.
• Synonym簡便かんべんWrittenWritten/formal prose for something convenient and handy, as in 「簡便な方法」. 「容易」 centers on low difficulty.
• Synonym安直あんちょくNeutralOften pejorative: a lazy, simplistic shortcut, as in 「安直な発想」. 「容易」 is neutral.
• SynonymイージーCasualA loanword for easy and relaxed, also sloppy or half-hearted; heard mostly in speech and in product names.
• Synonym造作ないぞうさないWrittenWritten/formal prose for something that takes no trouble; in everyday speech you would say 「簡単」.
• SynonymちょろいCasualSlang for something that's a piece of cake, also for people who are easy to fool; carries a dismissive tone.
• Synonym軽易けいいWrittenWritten/formal and rare; light and simple. In daily speech 「簡単」 is the natural choice.
• SynonymわけないNeutralColloquial for something that takes no effort at all, as in 「訳ない仕事」; it can also mean there is no way something is true.
• Synonymお安いおやすいNeutralIdiomatic in 「お安い御用」, marking a task as trivially easy; when it refers to a low price, that is a separate matter.
• Synonym楽チンらくチンCasualCasual slang for comfy and easy with a light, upbeat feel, as in 「持ち運びが楽ちん」; in formal settings say 「楽」.
• Synonym手軽いてがるいNeutralAn adjective for handy and effortless; rare, and 「手軽」 is what you would normally use.
• RelatedシンプルNeutralA loanword for clean, uncluttered simplicity, often for design or style. 「容易」 is about not being difficult.
• Related単純たんじゅんNeutralSimple in structure, and also simple-minded. 「容易」 centers on something being not hard to do.
• Antonym困難こんなんNeutralAntonym on the easy-hard axis: fraught with difficulty; leans written/formal.
• Antonym難しいむずかしいNeutralAntonym on the easy-hard axis: hard. The everyday word of choice.

For something not hard to do, 「容易」 itself is the written/formal choice; in everyday speech say 「簡単」, and for easy problems or content 「易しい」. For ease and low effort use 「楽」 or 「手軽」. Watch the pejorative 「安易」 and 「安直」 for taking the easy way out, and the casual 「ちょろい」「楽チン」「イージー」. The antonyms are 「難しい」 in daily use and 「困難」 in formal prose.

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

1. 何なんかをするのに容易たやすいこと。
2. 何なんかをするのに容易たやすいさま。