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


The company has an ironclad policy against revealing secrets to competitors. He has an ironclad alibi.

Recent Examples on the Web: Adjective

Most troublingly, the decline is steepest in small towns and rural areas whose communities were once ironclad. The Economist, "What the mighty Dolphins say about America," 1 Aug. 2019 In the earliest days—the days of Loie Fuller, Isadora Duncan, Ruth St. Denis, and then, in the next generation, Charles Weidman, Doris Humphrey, and others—the system was pretty ironclad. Joan Acocella, The New Yorker, "Can Modern Dance Be Preserved?," 24 June 2019 What’s constant is that an otherwise ironclad rule of life gets flipped to glorious effect. Spencer Kornhaber, The Atlantic, "Cruising in the Age of Consent," 19 June 2019 Notwithstanding this leakiness in the export ban, Mr Trump’s G20 concession is a sign that America’s commitment to containing Huawei is not ironclad. The Economist, "Donald Trump eases off Huawei as firms discover holes in his export ban," 4 July 2019 Meanwhile, despite their many letters, warm salutations and shared affection for the architect, Zanco's grip on Barragán's archives is ironclad, her resolve unshakable. Barbara Vandenburgh, azcentral, "In 'The Proposal,’ filmmaker seeks to free the work of a renowned Mexican architect," 19 June 2019 But Catherine, her aunt and manager, stymies her ambitions both with an ironclad contractual agreement and with a sleazy doctor who keeps Ashley on a diet of docility-ensuring drugs. Spencer Kornhaber, The Atlantic, "Black Mirror’s Miley Cyrus Episode Isn’t That Far-Fetched," 6 June 2019 The deep contrast between the two shows that the song itself was ironclad but not inert; that even the most hallowed of recordings could even be improved on with inventiveness and sheer force of charisma. Andrew R. Chow, Time, "Yesterday’s Beatles Covers Don’t Come Together. Here’s How the Movie Could Have Done Them Justice," 28 June 2019 Too many cases involving potential felonies are resolved through civil settlements that include ironclad NDAs. David Von Drehle, Twin Cities, "David Von Drehle: Jeffrey Epstein’s scandal of secrecy points to a creeping rot in the American justice system," 19 June 2019

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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Statistics for ironclad

Last Updated

14 Aug 2019

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Time Traveler for ironclad

The first known use of ironclad was circa 1847

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English Language Learners Definition of ironclad

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

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More from Merriam-Webster on ironclad

Rhyming Dictionary: Words that rhyme with ironclad

Spanish Central: Translation of ironclad

Nglish: Translation of ironclad for Spanish Speakers Encyclopedia article about ironclad

Comments on ironclad

What made you want to look up ironclad? Please tell us where you read or heard it (including the quote, if possible).


to make a temporary encampment

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