The Collaborative International Dictionary of English v.0.48:

Aryan \Ar"yan\ ([aum]r"yan or [a^]r"[i^]*an), n. [Skr. [=a]rya
   excellent, honorable; akin to the name of the country Iran,
   and perh. to Erin, Ireland, and the early name of this
   people, at least in Asia.]
   1. One of a primitive people supposed to have lived in
      prehistoric times, in Central Asia, east of the Caspian
      Sea, and north of the Hindu Kush and Paropamisan
      Mountains, and to have been the stock from which sprang
      the Hindu, Persian, Greek, Latin, Celtic, Teutonic,
      Slavonic, and other races; one of that ethnological
      division of mankind called also Indo-European or
      Indo-Germanic.
      [1913 Webster]

   2. The language of the original Aryans. [Written also
      Arian.]
      [1913 Webster]

   3. (Nazism) a non-Jewish caucasian of Nordic stock; -- a
      classification used by Nazis, having no anthropological
      basis. [Written also Arian.]
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Arian \Ar"ian\, a. & n. (Ethnol.)
   See Aryan.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Arian \A"ri*an\, a. [L. Arianus.]
   Pertaining to Arius, a presbyter of the church of Alexandria,
   in the fourth century, or to the doctrines of Arius, who held
   Christ to be inferior to God the Father in nature and
   dignity, though the first and noblest of all created beings.
   -- n. One who adheres to or believes the doctrines of Arius.
   --Mosheim.
   [1913 Webster]