Why is Oriental Orthodox called "Oriental"?

The Oriental Orthodox Church is the non-Chalcedonian branch formed as a result of the Chalcedonian controversy (see [*GotQuestion* article](https://www.gotquestions.org/Oriental-Orthodox-Church.html)) . I am curious where the name "Oriental" comes from for them, as this means "eastern" in Latin, and is therefore confusingly similar to the Eastern Orthodox. Most of them are Coptic (Egyptian) and Ethiopian, which makes them to the south of the Eastern Orthodox parts of the world, not to the east. So why was the term "Oriental" chosen?