to say to each other; to exchange (jokes, comments, etc.)
to quarrel; to dispute
二人は言い合ったまま帰った。
The two of them went home without resolving their argument.
朝から言い合っているのが聞こえてくる。
You can hear them arguing since this morning.
友達と言い合うのは珍しい。
It's rare for me to argue with friends.