The Collaborative International Dictionary of English v.0.48:

Iranian \I*ra"ni*an\, a.
   Of or pertaining to Iran. -- n. A native of Iran; also, the
   Iranian or Persian language, a division of the Aryan family
   of languages, the modern version of which is called Farsi.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Persian \Per"sian\, n.
   1. A native or inhabitant of Persia.
      [1913 Webster]

   2. The language spoken in Persia. Ancient Persian of the 3rd
      to 10th centuries is also called Pahlavi, and modern
      Persian is also called Farsi.
      [1913 Webster + PJC]

   3. A thin silk fabric, used formerly for linings. --Beck.
      [1913 Webster]

   4. pl. (Arch.) See Persian columns, under Persian, a.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Farsi \Far"si\ (f[aum]r"s[-e]), prop. n.
   The language spoken in modern Iran; modern Persian. It is
   written in the Arabic alphabet.
   [PJC]

WordNet (r) 3.0 (2006):

Farsi
    n 1: a person of Iranian descent; "many Farsi emigrated to India
         near Bombay"
    2: the language of Persia (Iran) in any of its ancient forms
       [syn: Persian, Farsi]