ironsides

A cuirassier or cuirassiers; also, hardy veteran soldiers; — applied specifically to Cromwell’s cavalry.

A nickname for the U.S.S. Constitution, a sailing ship which fought in the American Revolutionary war, and now functions as a floating museum in Boston harbor. It was given its nickname because cannonballs bounced off its hard wooden sides.

English general and statesman who led the parliamentary army in the English Civil War (1599-1658)