How to say "someone" in Japanese

• ひとJLPT N5approx.Common
  nounThe ordinary noun 'person'. It matches 'someone' when you simply mean a particular but unnamed person; for the purely indefinite pronoun 'someone, somebody', 誰か is the usual word.
  この人ひとは画家がかだ！↗

  This fellow is an artist!
• 誰かだれかJLPT N5approx.Common
  pronounThe default word for the indefinite pronoun 'someone, somebody': an unspecified person in statements and questions alike. If you just need to say 'someone' with no particular nuance, this is it.
  「誰だれか車くるまの中なかにいるのですか」「トムがいます」↗

  "Who is in the car?" "Tom is."
• どなたかCommon
  nounThe respectful (sonkeigo) counterpart of 誰か, used when politely referring to or addressing an unknown person, as in service announcements or questions to strangers. Usually written in kana alone.
  留守るす中ちゅうどなたか見みえましたか。↗

  Was anybody here while I was out?
• 一人物いちじんぶつCommon
  nounReally means 'one person' or 'a single character, figure' — it singles out or counts an individual rather than standing for an unspecified one. Seldom the word you want for plain 'someone'.

Use 「誰か」 for the plain indefinite pronoun 'someone', and 「どなたか」 when respect is called for; 「ひと」 is really the noun 'person', while 一人物 means 'one person or character', so neither is the everyday choice.

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

• ひとperson
• 誰かだれかsomeone
• どなたかsomeone
• ある人あるひとsomeone
• ひとかどの人物ひとかどのじんぶつsomeone (important)
• 何者かなにものかsomeone
• ひとかどの人間ひとかどのにんげんsomeone (important)
• 誰ぞだれぞsomeone
• 一人物いちじんぶつone person
• 然る者さるものcertain person (e.g. whose name cannot be disclosed)