iron·​clad | \ ˈī(-ə)rn-ˈklad How to pronounce ironclad (audio) \

Definition of ironclad

 (Entry 1 of 2)

1 : sheathed in iron armor used especially of naval vessels
2 : so firm or secure as to be unbreakable: such as
a : binding an ironclad oath
b : having no obvious weakness an ironclad case against the defendant


iron·​clad | \ ˈī(-ə)rn-ˌklad How to pronounce ironclad (audio) \

Definition of ironclad (Entry 2 of 2)

: an armored naval vessel especially of the mid to late 19th century

Examples of ironclad in a Sentence

Adjective The company has an ironclad policy against revealing secrets to competitors. He has an ironclad alibi.
Recent Examples on the Web: Adjective This weird series of events comes months after EA Sports' ironclad hold on the NFL's exclusive video game license came to an end. Sam Machkovech, Ars Technica, "Madden NFL’s technical problems were on full display in ESPN championship," 18 May 2020 Yet even at those inviting numbers, buyers were hard to find, a reflection of misplaced fears of a return to 1970s-style inflation despite unmistakable evidence that the Federal Reserve had made an ironclad commitment to price stability. Tom Saler, Milwaukee Journal Sentinel, "Tom Saler: Is the second half of the 'V' on its way? Investors seem to think so," 12 May 2020 Errol became such a constant and comforting fixture in their lives that the Brooks family instituted an ironclad rule. Los Angeles Times, "Column: Longtime Dodger Stadium ticket taker leaves a lasting impression on one family," 6 May 2020 In Berlin, a nurse in an intensive care unit who prefers to be called Nico because he’s not authorized to speak to the news media loves working with patients, and the undersupply of nurses means ironclad job stability. Lenora Chu, The Christian Science Monitor, "‘The doctor won’t see you now.’ Rethinking health care delivery in a crisis.," 6 Apr. 2020 Not enough to declare an ironclad correlation between the two. Zach Osterman, Indianapolis Star, "IU basketball player review: Justin Smith a key piece in promising frontcourt puzzle," 26 Mar. 2020 Of course, the notion of truth seems to have gone from ironclad to fluid in some people’s minds. Bill Goodykoontz, azcentral, "Scott Pelley of '60 Minutes' thinks journalism might be able to save America. Here's why," 13 Jan. 2020 Here’s one surprising company that would not make an ironclad commitment: the auto lending giant Ally Bank, which was the beneficiary of a federal bailout during the last financial crisis. Ron Lieber, New York Times, "Which Consumer Lenders Are (and Aren’t) Helping the Most," 17 Mar. 2020 The show has reached the status of ironclad Indianapolis tradition. Domenica Bongiovanni, Indianapolis Star, "'Frankenstein' and Mary Lincoln: Here's Indiana Repertory Theatre's 2020-2021 season," 11 Mar. 2020 Recent Examples on the Web: Noun During the Civil War, Eads won a contract to build Union ironclads. Mike Scott,, "Meet the man who tamed the Mississippi -- and saved the port of New Oreans," 1 May 2018 In 1862, during the Civil War, the ironclads USS Monitor and CSS Virginia (formerly USS Merrimac) clashed for five hours to a draw at Hampton Roads, Va., "This day in history," 9 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ironclad.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ironclad


circa 1847, in the meaning defined at sense 1


1862, in the meaning defined above

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The first known use of ironclad was circa 1847

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Last Updated

4 Jun 2020

Cite this Entry

“Ironclad.” Dictionary, Merriam-Webster, Accessed 6 Jun. 2020.

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More Definitions for ironclad


How to pronounce ironclad (audio)

English Language Learners Definition of ironclad

: not able to be changed
: too strong to be doubted or questioned

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