How to say "so-and-so" in Japanese

• なんとかJLPT N3approx.Common
  expressionStands in for a name or thing that escapes you or stays vague — 'what's-his-name,' 'something or other.' A conversational filler when the exact term will not come to mind; normally written in kana.
• 何々なになにJLPT N2approx.Common
  pronounCovers 'so-and-so' and especially 'such and such': a generic stand-in for names or items left unsaid, fitting when enumerating or speaking in general terms.

Both stand in for unspecified names or things: reach for 「なんとか」 when a particular name or word escapes you or stays vague, and for 何々 when you mean 'such and such,' referring to or listing items generically.

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

• なんとかsomething
• 誰々だれだれso-and-so
• 某々ぼうぼうso-and-so
• うんたらかんたらsomething-something
• うんたらsomething-something
• かんとかsomething
• どうたらこうたらsomething-something (e.g. platitudes, waffling)
• どうたらsomething-something (e.g. platitudes, waffling)
• 何々なになにso-and-so