How to say "fishy" in Japanese

• 生臭いなまぐさいJLPT N1approx.Common
  i-adjectiveThe literal odor sense: smelling of fish, or of blood. Use it when something — a kitchen, your hands, the water — actually smells of fish; it is not the word for the suspicious sense.
• 変へんJLPT N4approx.Common
  na-adjectiveA marginal match: it means strange, odd, peculiar, weird, so it covers 'fishy' only as in 'something fishy is going on', without implying deceit; for real suspicion use 怪しい or 臭い.
  そのオレンジは後味あとあじが変へんだった。↗

  The orange left a strange taste in my mouth.
• 怪しいあやしいJLPT N2approx.Common
  i-adjectiveThe straightforward word for the figurative sense: suspicious, dubious, questionable, dodgy. Use it for people, stories, deals, or behavior that seem fishy — that you cannot quite trust.
  みんな奴やつは怪あやしいと思おもっている。↗

  We are all suspicious about him.
• 臭いくさいJLPT N3approx.Common
  i-adjectiveAlso covers the figurative sense, casting suspicion as a smell — much like English 'something smells fishy'. Use it for a story, excuse, or deal that seems dubious.
  あいつが臭くさい。↗

  He looks suspicious.

For the literal smell of fish or blood use 「生臭い」; for the figurative 'suspicious' sense choose 「怪しい」 or 「臭い」, while 変 only says something seems odd, without implying dishonesty.

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

• 生臭いなまぐさいsmelling of fish
• 変へんstrange
• 怪しいあやしいsuspicious
• いんちき臭いいんちきくさいfishy
• うろんsuspicious-looking
• 訝しいいぶかしいsuspicious
• 胡散臭いうさんくさいsuspicious-looking
• 臭いくさいsuspicious