How to say "unavailable" in Japanese

• 無効むこうJLPT N1approx.Common
  no-adjective, na-adjectiveA common word meaning essentially invalid, void or ineffective: something has been cancelled or rendered null, like a voided contract. Pick it when 'unavailable' really means invalid, not unobtainable.
  脅迫きょうはくのもとになされた約束やくそくは無効むこうだ。↗

  A promise given under a threat is worthless.
• 入手不可能にゅうしゅふかのう
  na-adjectiveUse when 'unavailable' means unobtainable: the item, goods or information simply cannot be got. The fuller-written counterpart of 入手不可, which is the version tied especially to stock.
• 入手不可にゅうしゅふか
  na-adjectiveMeans unobtainable, used especially of stock and the like: goods that cannot be procured or are out of stock. The shortened form of 入手不可能.
• 対応不可たいおうふか
  no-adjectiveCovers 'unavailable' on the response side: a person, office or service cannot deal with a request or demand — it is impossible to fulfil. Not about goods you cannot obtain.
• 使用不可しようふか
  na-adjectiveFor 'unavailable' meaning disabled or unusable: the thing itself cannot be used, as with a function or facility that is out of service or switched off.

Split 'unavailable' by sense: something declared invalid or void is 無効; something you cannot obtain is 入手不可能 or, especially of stock, 入手不可; a request that cannot be handled is 対応不可; something disabled from use is 使用不可.

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

• 無効むこうinvalid
• 入手不可能にゅうしゅふかのうunavailable
• 入手不可にゅうしゅふかunavailable (stock, etc.)
• 対応不可たいおうふかunavailable
• 使用不可しようふかunavailable