無用|むようmuyou[0]heiban (flat)

1. na-adjective, nounuseless; futile
   電気でんきのために、ろうそくは我々われわれの生活せいかつにほとんど無用むようになった。↗

   Electricity made candles of little use in our life.
2. na-adjective, noununnecessary; needless
   あせって仕事しごとを仕上しあげようとすれば、無用むような間違まちがいを犯おかす。↗

   When we rush to complete our work, we make needless errors.
3. na-adjective, nounnot on business; unrelated; unauthorised; unauthorized
   無用むようの立ち入たちいり禁止きんし。↗

   No admittance except on business.
4. na-adjective, nounprohibited; banned; forbidden

• Synonym無駄むだNeutralRefers to waste or wasted effort; the most common word in speech. 「無用」 leans written, stressing that something is useless or unneeded, as in notices like 「立入無用」.
• Synonym徒あだNeutralSame word as above; 「徒」 is simply an alternative writing. Refers to futile, wasted effort, as in 「無駄足」.
• Synonym無益むえきWrittenWritten/formal prose for bringing no benefit or good; 「無用」 stresses that something is simply not needed.
• Synonym無意味むいみNeutralMeans 'meaningless, pointless'; 「無用」 is about lacking use or being unnecessary.
• SynonymだめNeutralMeans no good or not allowed and is the most common word in speech; 「無用」 leans toward written notices.
• Synonym不必要ふひつようNeutralMeans unnecessary with a formal air; 「無用」 is terser and common in notices and phrases like 「無用な心配」.
• Synonym不要ふようNeutralMeans not needed, as in 「予約不要」; 「無用」 can also mean 'no need', sometimes with a discouraging tone.
• Synonym徒爾とじWrittenWritten/formal prose and rare; means futile and unprofitable.
• Related虚しいむなしいNeutralMeans empty or futile with a wistful, emotional tinge; 「無用」 is more objective.
• Related余計よけいNeutralMeans superfluous or meddlesome, as in 「余計なお世話」; 「無用」 leans written.
• Related不毛ふもうNeutralMeans barren land or, figuratively, a discussion yielding no results; 「無用」 stresses lack of use.
• Related無効むこうNeutralMeans invalid or void, without effect; 「無用」 stresses lacking use.
• Related無価値むかちNeutralMeans utterly worthless, without value; 「無用」 stresses having no use.
• Related不用ふようNeutralRefers to things discarded or no longer used, as in 「不用品」; 「無用」 stresses that something is unnecessary.
• Related甲斐無いかいないWrittenWritten/formal prose for having no effect or being in vain; 「無用」 stresses that something is not needed.
• Related詮無いせんないWrittenWritten/formal prose and rare; means there is no help for it — a different focus from 「無用」.
• Related益体もないやくたいもないWrittenWritten/formal prose and rare; means utterly useless and silly.
• Related甲斐なしかいなしWrittenWritten/formal prose and rare; means worthless, useless, hopeless.
• Antonym有用ゆうようNeutralAntonym: means useful, the opposite of useless 「無用」.
• Antonym必要ひつようNeutralAntonym: means necessary, the opposite of unneeded 「無用」.

Use 「無用」 for things that serve no purpose or for terse notices saying something is unnecessary or forbidden, as in 「問答無用」 and 「心配無用」. For wasted effort in everyday speech say 「無駄」; for 'not needed' say 「不要」; for 'superfluous' say 「余計」; for 'no good' say 「駄目」; for 'useful' say 「有用」.

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

1. なくてもよいもの。いらないこと。
2. 役やくに立たたないこと。
3. 用ようのないこと。
4. してはいけないこと。禁止きんし。