不要|ふようfuyou[0]heiban (flat)

1. na-adjective, no-adjectiveunnecessary; unneeded
   彼かれらは不用ふようの物ものは捨すてた。↗

   They discarded unnecessary things.

• Synonym無用むようWrittenWritten/formal prose. Covers useless or futile things and prohibitions on signs like 「天地無用」「問答無用」; leans toward meaningless, while 「不要」 stresses simply not needed.
• Synonym不必要ふひつようNeutralNeutral. Says simply that there is no need, e.g. 「不必要な出費」; note that 「不要」 can also imply the thing is superfluous and gets in the way.
• Related余計よけいCasualColloquial. Superfluous or 'even more', e.g. 「余計なお世話」; it frequently sounds irritated, stressing that something is unwanted or uncalled-for.
• Related過剰かじょうWrittenWritten/formal prose. Refers to excess, e.g. 「過剰包装」; it stresses going beyond a proper amount rather than simply being unneeded.
• Related過多かたWrittenWritten/formal prose. Means too much, e.g. 「情報過多」; it focuses on quantity exceeding a limit, not on whether something is needed.
• Antonym必要ひつようNeutralNeutral. Means necessary or needed; it is the direct opposite of 「不要」 in its sense of not being needed.
• Antonym必須ひっすWrittenWritten/formal prose. Means essential or required, e.g. 「必須科目」; it stands opposite 「不要」 in the sense of dispensable.
• Antonym所要しょようWrittenWritten/formal prose. Means required, e.g. 「所要時間」; opposite to 「不要」 in meaning, but the two are not usually set directly against each other.

Use 「不要」 for things not needed or not required, as in 「予約不要」「不要品」「不要不急」. For meaningless or futile use 「無用」, for superfluous 「余計」, for excess 「過剰」; the opposites are 「必要」 and 「必須」.

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

1. 必要ひつようでないこと。余計よけいであること。あることをするのに、なくてもかまわない物ものや事ことで、あると却かえって邪魔じゃまになるという意味いみを含ふくむ。