It literally translates to "God keep you."
Here are some other ways to say goodbye in Persian, depending on the situation:
* خداحافظی (khodahafezi): More formal than "khodahafez".
* بدرود (bedrood): A more poetic and formal goodbye.
* تا بعد (ta ba'd): Literally "until later", used for informal goodbyes.
* خدانگهدار (khodanegedar): "May God keep you"
* به سلامت (be salamat): "In good health"
* خدانگهدارتون (khodanegedartun): "May God keep you" (plural form)
The specific choice of word can depend on the context, the relationship between the speakers, and the level of formality.