man-at-arms definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
noun pl. men-at-arms
a soldier; esp., a heavily armed medieval soldier on horseback
man-at-arms definition by American Heritage Dictionary
noun pl. men-at-arms men-at-arms
A soldier, especially a medieval cavalryman supplied with heavy arms.