A person from Tatarstan; or the Turkic language of Tatarstan. It is often written Tartar, which is probably an erroneous adaptation of the name to Greek Tartaros, an abode of the dead.

Historically, applied to any of various steppe peoples. Modern Tatarstan, whose capital is at Kazan, was known as Kazan Tartary. Crimea was also inhabited by Tatars, until their deportation by Stalin, and was earlier known as Crim Tartary.

The word 'tartar' in the sense of 'termagant, fierce person' derives from memories of these hordes.