tsar

thumb|Simeon I of Bulgaria, the first Bulgarian tsar and the first person who bore the title "tsar", by [[Alphonse Mucha|alt=Alphonse Mucha's The Slav Epic cycle No.4: Tsar Simeon I of Bulgaria (1923)]] thumb|Reception of the Tsar of Russia in the Moscow Kremlin, by [[Ivan Makarov]] thumb|Crowning of Stefan Dušan, [[Emperor of the Serbs, as tsar, by Paja Jovanović]]

Tsar (; also spelled czar, tzar, or csar; ; ; ) is a title historically used by some Slavic monarchs. The term is derived from the Latin word caesar, which was intended to mean emperor in the European medieval sense of the term—a ruler with the same rank as a Roman emperor, holding it by the approval of another emperor or a supreme ecclesiastical official—but was usually considered by Western Europeans to be equivalent to "king".