An exchange (of things, words, messages); back-and-forth communication such as emails or arguments; used as a noun and as a 'suru' verb.
先生とメールでやりとりをして、質問に答えてもらった。
I exchanged emails with the teacher and got my questions answered.
会議では活発な意見のやりとりがあった。
There was an active exchange of opinions at the meeting.
子ども同士のちょっとしたやりとりが問題になった。
A minor back-and-forth between the children became an issue.