Verb (5-dan, う, transitive)
1. to say to each other; to exchange (jokes, comments, etc.)
お互いの考えを言い合えた。We were able to exchange our thoughts with each other.
Verb (5-dan, う, intransitive)
2. to quarrel; to dispute
この間も彼は激しくそのことで社長と言い合っていたとか。I heard he had a heated argument with the boss about that just the other day, too.