expression, godan verb (-u)
get along well with; be on good terms with
Idiomatic expression meaning to have a good rapport or chemistry with someone. Often used in the negative form 馬が合わない to indicate incompatibility.
彼とは馬の合う仲で、一緒に仕事をするのが楽しい。
He and I get along well, so working together is enjoyable.
I just do not get along with that person.