The xiphos (ξίφος) is an double-edged, single-hand sword used by the ancient Greeks. It was a primary battlefield weapon for the Greek armies along with the spear or javelin.

The straight, double-edged design of the xiphos lends it the same overall martial versatility found in the swords used by infantry until the firearm supplanted the sword on the battlefield. Its design lent itself to cutting and thrusting.

Because of the nature of mounted combat, Xenophon recommended using the curved makhaira for cavalry in On Horsemanship 12:11.