1.
each person, one by one
Every individual person, considered separately.
一人一人に聞いた。
I asked each person.
一人一人に挨拶した。
I greeted each person individually.
生徒一人一人の個性を大切にする。
We value each student's individuality.
先生は一人一人の名前を呼んで出席を取った。
The teacher called each person's name to take attendance.
一人一人の力は小さいが、集まれば大きな力になる。
Each individual's power may be small, but together it becomes a great force.
一人一人 emphasizes treating each individual separately within a group. It functions as both a noun and an adverb.
ALTERNATIVE WRITING:
- 一人一人 (all kanji)
- 一人ひとり (mixed — common in print)
- ひとりひとり (all hiragana)
COMMON PATTERNS:
- 一人一人に: to each person
- 一人一人の + noun: each person's ~
- 一人一人が: each person (as subject)
SIMILAR EXPRESSIONS:
- それぞれ: each, respectively (general — can apply to things too)
- 各々: each one (formal/literary)
- 個々に: individually (more abstract)
- めいめい: each person (slightly old-fashioned)