[adjective ahy-ern-klad; noun ahy-ern-klad]


covered or cased with iron plates, as a ship for naval warfare; armor-plated.
very rigid or exacting; inflexible; unbreakable: an ironclad contract.


a wooden warship of the middle or late 19th century having iron or steel armor plating.

Nearby words

  1. iron-pumper,
  2. iron-sick,
  3. iron-storage disease,
  4. ironbark,
  5. ironbound,
  6. irondequoit,
  7. irone,
  8. ironer,
  9. ironfisted,
  10. ironhanded

Origin of ironclad

First recorded in 1850–55; iron + clad1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ironclad

British Dictionary definitions for ironclad


adjective (ˌaɪənˈklæd)

covered or protected with ironan ironclad warship
inflexible; rigidan ironclad rule
not able to be assailed or contradictedan ironclad argument

noun (ˈaɪənˌklæd)

a large wooden 19th-century warship with armoured plating
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for ironclad



1852, of warships, American English, from iron (n.) + clad. Of contracts, etc., 1884. As a noun meaning "iron-clad ship," it is attested from 1862.

Online Etymology Dictionary, © 2010 Douglas Harper