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A centurion (; Latin: centurio [kɛn̪ˈt̪ʊrioː], pl. centuriones; Ancient Greek: κεντυρίων, romanized: kentyríōn, or Ancient Greek: ἑκατόνταρχος, romanized: hekatóntarkhos) was a professional non-commissioned officer in the Roman army who commanded a group of soldiers called a centuria or "century".
The term centurion is derived from the Latin word centurio, which itself originates from centum, meaning "hundred." Initially, centurions were commanders of a unit of roughly 100 soldiers, although the exact number varied over time and by period. The concept of the centurion emerged during the early Roman Republic (509–27 BCE), when Rome's military was based on citizen-soldiers organized into centuries (centuriae), units of 100 men within the Roman legion (legio).
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