Emphasizes a repeated or ongoing alternation between people or groups. Often used adverbially with に.
See also: 交代
子供たちは交代交代にブランコに乗った。
The children took turns on the swing.
彼らは交代交代で運転した。
They took turns driving.
Reduplication of 交代 (こうたい, 'alternation, shift change'), emphasizing a repeated or ongoing alternation.