عربي term (edited): ��������

قال صاحب المنجد: الطيلسان كساء أخضر يلبسه الخواص من المشايخ والعلماء، وهو من لباس العجم

According to Hans Wehr's description, it is a shawl-like garment worn over the head and shoulders.

I believe it should not be translated, as the term seems to be used in this context in reference to a peculiar garment. It may be a good idea to include a brief description as translator's note, depending on the nature of the project and the client's preferences.

In some other contexts, the term is used generically as a name for any outer garment or cloak. An example of that is:

رب ليل كأنه الصبح في الحسن وإن كان أسود الطيلسان

In this kind of context, I would translate it generically as "cloak."