1
general::
On a friendly footing, as in I'm on good terms with the manager, so I'll ask him to help you. Shakespeare used the phrase slightly differently in King Lear (1:2): "Parted you in good terms?" The precise current usage was first recorded in 1669. Also see ON SPEAKING TERMS.
American Heritage Idioms
2
general::
Phrase(s): on good terms (with someone)
friendly with someone; able to interact well and be friends with someone. • Bill is on good terms with the people he works with. • We are not on very good terms and don’t speak to each other much.
McGrawhill's American Idioms And Phrasal Verbs