n. A non-Muslim, especially a Christian, an infidel; especially as used by Turkish people with particular reference to Christians such as Greeks, Armenians, Bulgarians, Serbs and Assyrians.
the GNU version of the Collaborative International Dictionary of English
n. An infidel; -- a term applied by Turks to disbelievers in the Mohammedan religion, especially Christrians.
The Century Dictionary and Cyclopedia
n. An infidel: used by the Turks to designate an adherent of any religion except the Mohammedan, more particularly a Christian, and so commonly that it does not necessarily imply an insult.
Word Usage
"He spoke apologetically to the holy man, alluded to the "giaour" more than once, and proceeded to give Dick"