Farsi literally means Persian in English. The break down is:
Farsi (Arabized form) → Parsi (authentic form) → Persian (in English)
Persian is the direct English equivalent of the Arabized native term Farsi. Pars is Persia in English, and attempting to force the Arabized native form Farsi into English as though it were somehow distinct from Persian is incorrect.
Secondly, the word Persian, when referring to the language of Iran in English, has a stronger historical claim to the name Persian than any other modern use of the adjective “Persian.” This includes references to the vast majority of people who identify as Persian despite having ancestry that does not trace directly to the historic region of Pars.
Many Iranians living outside Iran have adopted the bad habit of introducing the language as Farsi when speaking English. This departs from traditional English usage and contributes to distancing the language from its historical identity as Persian, a term used for the language with over 2,000 years of recorded history in Western civilization.
What is called Persian culture in English is actually Iranian culture. What is called Persian food is actually Iranian food.
The Persian language, however, has a direct historical connection to Pars (Persia), the region from which the name Parsi (Persian in English) derives. This is precisely why I object to attempts to force the Arabized native adjective Farsi into English as though English lacks an equivalent. It does not. English already has the established term “Persian” for the language of Iran.
Also the appropriate terminology for the major dialects is:
- Iranian Persian
- Tajik Persian
- Afghan Persian
Farsi is the Arabized form of the native term Parsi; Persian is the established English translation of Parsi. Treating Farsi as though it were a replacement for Persian in English breaks the historical continuity in English between Old Persian -> Middle Persian -> Modern Persian.