also: ちくいつ
one by one; in detail; minutely
Used when going through items, points, or details individually and exhaustively. Often appears with verbs like 説明する, 報告する, 調べる, or 指摘する.
Please explain each problem point one by one.
He noted down the meeting details minutely.
He reported the details of the meeting one by one.
The teacher explained the procedure step by step.
We need to check the inventory item by item.
Kana spelling is common in everyday writing, especially when the kanji is not needed.