ironclad
Americanadjective
-
covered or cased with iron plates, as a ship for naval warfare; armor-plated.
-
very rigid or exacting; inflexible; unbreakable.
an ironclad contract.
noun
adjective
-
covered or protected with iron
an ironclad warship
-
inflexible; rigid
an ironclad rule
-
not able to be assailed or contradicted
an ironclad argument
noun
Other Word Forms
Noun Inflected Forms
Etymology
Origin of ironclad
Explanation
Something ironclad is either covered in iron for protection or protected in a different way. An ironclad guarantee can’t be broken or taken back. Originally, this word was very literal: an ironclad battleship was clad (covered) in iron. Since then, this word is more metaphorical, though it still applies to things you can trust. An ironclad contract is unbreakable. An ironclad promise can be believed wholeheartedly. If you were arrested on ironclad charges, you’re going to be found guilty.
Vocabulary lists containing ironclad
The American Civil War
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President Trump's First State of The Union Address (2018)
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Courage to Soar
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
After their private meeting, Zelensky thanked the UK for its "ironclad" support and revealed he planned to invite the King for a state visit to Ukraine in the future.
From BBC ● Jun. 8, 2026
Five years ago, a seemingly ironclad test of whether something was conscious was to see if you could have a conversation with it.
From Science Daily ● Jun. 5, 2026
So oil companies who go in need to have ironclad legal terms that aren’t just about a change of control in Venezuela.
From Barron's ● Jan. 7, 2026
Its defense agreement fell short of the ironclad mutual-defense pact it wants.
From The Wall Street Journal ● Nov. 21, 2025
One of Momma Biles’s ironclad rules was that no matter where we were or what we were doing, once the streetlights came on, it was time to head home.
From "Courage to Soar" by Simone Biles
These days, substitute nuclear intercontinental ballistic missiles, strategic bombers, aircraft carriers, and similar "modern" weapons for the ironclads of his era and the sentiment rings at least as true as it did then.
From Salon ● Mar. 22, 2023
He also corresponded with French shipyards on the design of Confederate ironclads.
From Science Magazine ● Sep. 2, 2021
"A lot of these ironclads are built by house carpenters, they're not built by shipwrights," said Jeff Seymour, historian and curator for the National Civil War Naval Museum in Columbus.
From US News ● Aug. 16, 2015
On March 8 and 9, 1862, the Battle of Hampton Roads pitted the Union’s Monitor against the Confederate ironclad Virginia, the first battle between ironclads.
From Washington Times ● Aug. 1, 2015
Mebby I oughtnt say we took it becus it was the ironclads that done it.
From "Across Five Aprils" by Irene Hunt
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
