A sabre (French: [ˈsabʁ], or saber in American English) is a type of backsword with a curved blade associated with the light cavalry of the early modern and Napoleonic periods. Originally associated with Central European cavalry such as the hussars, the sabre became widespread in Western Europe during the Thirty Years' War. Lighter sabres also became popular with infantry of the early 17th century. In the 19th century, models with less curving blades became common and were also used by heavy cavalry.
The military sabre was used as a duelling weapon in academic fencing in the 19th century, giving rise to a discipline of modern sabre fencing (introduced in the 1896 Summer Olympics) loosely based on the characteristics of the historical weapon in that it allows for cuts as well as thrusts.
The English sabre is recorded from the 1670s, as a direct loan from French, where the sabre is an alteration of sable, which was in turn loaned from German Säbel, Sabel in the 1630s. The German word is on record from the 15th century, loaned from Polish szabla, which was itself adopted from Hungarian szabla (14th century, later szablya).
The spread of the Hungarian word to neighboring European languages took place in the context of the Ottoman wars in Europe of the 15th to 17th centuries. The spelling saber became common in American English in the second half of the 19th century.
The origin of the Hungarian word is unclear. It may itself be a loan from South Slavic (Serbo-Croatian сабља, Common Slavic *sablja), which would ultimately derives from a Turkic source. In a more recent suggestion, the Hungarian word may ultimately derive from a Tungusic source, via Kipchak Turkic selebe, with later metathesis (of l-b to b-l) and apocope changed to *seble, which would have changed its vocalisation in Hungarian to the recorded sabla (perhaps under the influence of the Hungarian word szab- "to crop; cut (into shape)".
Though single-edged cutting swords already existed in the Ancient world, such as the ancient Egyptian and Sumerian sickle swords, these (usually forward instead of backward curving) weapons were chopping weapons for foot soldiers.