Source : Webster's Revised Unabridged Dictionary (1913)

Citizen \Cit"i*zen\, a.
   1. Having the condition or qualities of a citizen, or of
      citizens; as, a citizen soldiery.

   2. Of or pertaining to the inhabitants of a city;
      characteristic of citizens; effeminate; luxurious. [Obs.]

            I am not well, But not so citizen a wanton as To
            seem to die ere sick.                 --Shak.

Citizen \Cit"i*zen\, n. [OE. citisein, OF. citeain, F. citoyen,
   fr. cit['e] city. See {City}, and cf. {Cit}.]
   1. One who enjoys the freedom and privileges of a city; a
      freeman of a city, as distinguished from a foreigner, or
      one not entitled to its franchises.

            That large body of the working men who were not
            counted as citizens and had not so much as a vote to
            serve as an anodyne to their stomachs. --G. Eliot.

   2. An inhabitant of a city; a townsman. --Shak.

   3. A person, native or naturalized, of either sex, who owes
      allegiance to a government, and is entitled to reciprocal
      protection from it.

   Note: This protection is . . . national protection,
         recognition of the individual, in the face of foreign
         nations, as a member of the state, and assertion of his
         security and rights abroad as well as at home. --Abbot

   4. One who is domiciled in a country, and who is a citizen,
      though neither native nor naturalized, in such a sense
      that he takes his legal status from such country.

Source : WordNet®

citizen
     n : a native or naturalized member of a state or other political
         community [ant: {foreigner}]