Alternation; occurring in turn or taking turns. Often used adverbially as '交互に'.
彼らは交互に休憩を取りながら作業した。
They worked while taking breaks alternately.
電車の座席は窓側と通路側が交互に並んでいる。
The seats on the train are arranged alternately by window and aisle.
赤と白の旗が交互に掲げられている。
Red and white flags are displayed alternately.