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circle
"correct"; "good"
*; _
period; full stop
handakuten (diacritic)
「〇」 has other readings with different meanings.
地図に〇をつけて場所を示す。
I mark locations on the map with circles.
答案に〇をつけてもらった。
I got a correct mark on my answer.
プライバシーを守るため〇で隠す。
I hide information with circles for privacy.