ironclad Meaning, Definition & Usage

  1. noun a wooden warship of the 19th century that is plated with iron or steel armor
  2. adjective satellite sheathed in iron plates for protection
  3. adjective satellite inflexibly entrenched and unchangeable
    brassbound.
    • brassbound traditions
    • brassbound party loyalists
    • an ironclad rule

WordNet

I"ron*clad` adjective
Definitions
  1. Clad in iron; protected or covered with iron, as a vessel for naval warfare.
  2. Rigorous; severe; exacting; as, an ironclad oath or pledge. Colloq.
I"ron*clad` noun
Definitions
  1. A naval vessel having the parts above water covered and protected by iron or steel usually in large plates closely joined and made sufficiently thick and strong to resist heavy shot.

Webster 1913