repetition; iteration — the act of repeating something (often used for practice, learning, or repeated processes).
反復練習によって技術が身につく。
You acquire skill through repetitive practice.
同じ工程の反復が品質向上につながった。
Repeating the same process led to improved quality.
先生は重要な点を反復して説明した。
The teacher explained the important points repeatedly.