Peltast their ranks (to allow the Persian cavalry through) and proceeded to deal blows (with swords) and throw javelins at them as they went through. Xenophon's description makes it clear that these peltasts were armed with swords, as well as javelins, but not with spears. When faced with a charge from the Persian cavalry they opened their ranks and allowed the cavalry through while striking them with swords and hurling javelins at them. They became the main type of Greek mercenary infantry in the 4th century BCE. Their equipment was less expensive than that of traditional hoplites and would have been
Thracian language (meaning "up") and based on several Thracic items, would have meant "upon", "up", and "Utaspios" is theorized to have meant "On horse(back)", parallel to ancient Greek "ephippos (epi-hippos)". The early Indo-European languages had more than one word for horse; for example Latin had "equus" from PIE "*ekwo-" and "mannus" ("a pony") from another IE root, later receiving "cabalus" as a loanword. In many cases in current Thracology, there is more than one etymology for a Thracian lexical item. For example, Thracian "Diana Germetitha" ("Diana" is from Latin while the epithet "Germetitha" is from Thracian) has two different proposed etymologies, "Diana