Anissa is a form used in French and Catalan (
Anisa in Spanish and Anisah in English) to transcript the Arabic feminine name Anisah, "friendly, affectionate" or "close friend". It is a very usual feminine name in Morocco, e.g.
Once, a Catalano-Moroccan girl named Anissa told me that, despite of the Arabic origin, in some Aragonese Mediaeval documents appears the form
Anisa as variant/derivated form of
Ana, but I haven't been able to find it.
Lumia
http://onomastica.mailcatala.com