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
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
President Trump's First State of The Union Address (2018)
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Courage to Soar
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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:
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
It also reaffirms the UK and Poland's "ironclad commitment" to Nato and speaks of migrant smuggling being a "shared challenge requiring joint solutions".
From BBC ● May 27, 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
The routine was ironclad, which put the weight of responsibility on Barack to either make it on time or not.
From "Becoming" by Michelle Obama
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
Quarstein is the chief development officer of the USS Monitor Foundation and has written three books about Civil War ironclads, as well as working on other topics and PBS documentaries.
From Washington Times ● Aug. 1, 2015
After all, wasn’t it true that it was not Grant who had been the victor at Fort Henry, but Admiral Foote and his ironclads?
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.
