绪斯同（希腊语 ξυστόν），是古代希腊骑兵所用来戳击的骑枪。这种骑枪长约3.5~4.25公尺，很可能因为过长的原因而需要两手持用，然而从庞贝城所发掘出来的亚历山大马赛克镶嵌画显示，绪斯同骑枪也可以用一手持用。绪斯同骑枪枪身由山茱萸木制成，枪末头也有一矛头，可用来保持平衡，或是当骑枪折断后可用来另一头继续战斗。

在一些描述古代马其顿伙友骑兵的文献中，绪斯同骑枪也经常被连带提起。当亚历山大大帝逝世后，马其顿重装骑兵因为是使用绪斯同骑枪的原因，而被称为绪斯同骑兵（xystophoroi）。

另外，因为当时尚未发明出马蹬，一些战史学家如富勒（J.F.C.Fuller）等认为，若骑兵持骑枪进行冲锋时，冲击的反作用力将会把骑手掀落马下，因此手持绪斯同骑枪的马其顿骑兵可能以投标枪的方式倒持（上手握持），枪身倚在肩膀上，当冲锋时将骑抢举起，从上向下往盾牌后面的敌兵猛刺（即Overhand Thrusting），之后骑枪顺势脱手，再拔剑战斗。但同样在亚历山大马赛克镶嵌画显示，手持绪斯同骑枪的亚历山大以低手握持方式进行攻击，同时画中一些骑兵以上手握持，可能绪斯同骑枪的握法随骑手喜好而定。

The xyston (Ancient Greek: ξυστόν "spear, javelin; pointed stick, goad") was a type of a long thrusting spear in ancient Greece. It measured about 3.5–4.25 meters (11.5–13.9 ft) long and was probably held by the cavalryman with both hands, although the depiction of Alexander the Great's xyston on the Alexander Mosaic in Pompeii (see figure), suggests that it could also be used single handed. It had a wooden shaft and a spear-point at both ends. Possible reasons for the secondary spear-tip were that it acted partly as a counterweight and also served as a backup in case the Xyston was broken in action. The xyston is usually mentioned in context with the hetairoi (ἑταῖροι), the cavalry forces of ancient Macedon. After Alexander the Great's death, the hetairoi were named xystophoroi (ξυστοφόροι, "spear-bearers") because of their use of the xyston lance. In his Greek-written Bellum Judaicum, the Jewish historian Flavius Josephus uses the term xyston to describe the Roman throwing javelin, the pilum.