A kilij (from Turkish kılıç, literally "sword") is a type of one-handed, single edged and moderately curved saber used by the Turks and related cultures throughout history starting from the late Hsiung-nu period to the time of the Avar Empire and the Göktürk Khaganate, Bulgarian Empire, Uyghur Khaganate, Seljuk Empire, Timurid Empire, Mamluk Empire, Ottoman Empire, and the later Turkic Khanates of Central Asia and Eurasian steppes. These blades evolved from Turko-Mongol sabers that had been used over all the lands invaded and/or influenced by the Turkic peoples.
The Turkish root verb "kır-" means "to break" with the suffix "-inç" makes "kır-ınç" (instrument for breaking) becomes kılınç, then kılıç.
The kilij became the symbol of power and kingdom. For example, Seljuk rulers carried the name (kılıç-arslan) means "sword-lion".
The Central Asian Turks and their offshoots begun using curved cavalry swords beginning from the late Hsiung-Nu period. The earliest examples of curved, single edged Turkish swords can be found associated with the late Hsiung-nu and Kok Turk empires. These swords were made of pattern welded high carbon crucible steel, generally with long slightly curved blades with one sharp edge. A sharp back edge on the distal third of the blade known as "yalman" or "yelman" was introduced during this period.
In the Early Middle Ages, the Turkic people of Central Asia came into contact with Middle Eastern civilizations through their shared Islamic faith. Turkic Ghilman slave-soldiers serving under the Umayyad and Abbasid Caliphates introduced "kilij" type sabers to all of the other Middle Eastern cultures. Previously, Arabs and Persians used straight-bladed swords such as the earlier types of the Arab saif, takouba and kaskara.