hundredman
A person overseeing one hundred others; (especially) a man overseeing a hundred-strong army.
historical
“By your command, Lord Bornhald.” The hundredman sounded only a little disappointed. Touching gauntleted fist to heart, he wheeled away toward the Tuatha’an encampment.
A centurion.
Coordinate term: (chiliarch) thousandman, thousandealdorman
Where it comes from
From Old English hundredmann, equivalent to hundred + -man.
Adapted from the Wiktionary entry hundredman (CC BY-SA 4.0).