Yes, centuria < centum '100'. Originally, just a 100 of anything, but soon, soldiers (in a legion), acres, and a finally 'one of the one hundred and ninety-three orders into which Servius Tullius divided the Roman people according to their property'.

A legio consisted of (usually) 10 cohorts of men (plus 300 cavalry). A cohort (lit. 'fenced-in') consisted of 3 maniples (lit. 'handful') or 6 centuries. Centurions were in charge of centuries, while legates were in charge of a legion. Those whacky Romans.