ironsides Meaning, Definition & Usage

  1. noun English general and statesman who led the parliamentary army in the English Civil War (1599-1658)
    Cromwell; Oliver Cromwell.
  2. noun a man of great strength or bravery
    ironside.

WordNet

I"ron*sides" noun
Definitions
  1. A cuirassier or cuirassiers; also, hardy veteran soldiers; -- applied specifically to Cromwell's cavalry. Old Ironsides. The U.S.S. Constitution, a ship which fought in the American Revolutionary war, and now functions as a museum in Boston harbor.

Webster 1913