How to say "detective" in Japanese

• 探偵たんていCommon
  nounThe ordinary word for a detective as a person — an investigator or sleuth. It covers both someone hired to look into a case and the sleuths of detective stories; choose this by default.
  彼女かのじょは彼かれを探偵たんていだと言いった。↗

  She described him as a detective.
• ディテクティブ
  nounA katakana borrowing of the English word, and a less common way to say 'detective'. It is seldom the word you want; for a detective in any sense, 探偵 is the usual choice.

For a detective in any sense — an investigator you hire or a sleuth in fiction — 探偵 is the common, ordinary word; 「ディテクティブ」 is only a less common katakana borrowing and rarely the word you need.

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

• 探偵たんていdetective
• ディテクティブdetective
• 刑事けいじ(police) detective
• 刑事でか(police) detective