How to say "outdated" in Japanese

• 古臭いふるくさいCommon
  i-adjectiveCovers the everyday, critical sense of outdated: something that feels stale, hackneyed, or behind the times. A common word for passing judgment on ideas, jokes, styles, or designs that strike you as dated.
  私は彼かれの古ふるくさい冗談じょうだんにうんざりした。↗

  I was bored with his old jokes.
• アウトオブデート
  na-adjective, nounA katakana borrowing of the English phrase 'out of date', with the same meaning. It is less common, however, and seldom the word you want for expressing 'outdated' in Japanese.
• 旧弊きゅうへい
  na-adjectiveA critical word for customs, institutions, and practices that are antiquated or outmoded — 'outdated' applied to established ways of doing things. Less common, and at home in serious discussion of society and its institutions.
  旧弊きゅうへいな人ひとは新あたらしい事ことになじめない。↗

  You can't teach an old dog new tricks.

Use 「古臭い」 for the everyday, critical sense of something feeling stale or behind the times; 旧弊 for antiquated customs or institutions; 「アウトオブデート」 is an uncommon loanword you will seldom need.

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

• 古臭いふるくさいstale
• アウトオブデートout-of-date
• 旧弊きゅうへいold-fashioned