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

The Deep South initially demanded slavery’s ironclad protection. David S. Reynolds, WSJ, "‘No Property in Man’ and ‘The War Before the War’ Review: The Fuse the Founders Lit," 22 Nov. 2018 In one key shift, investors realized bonds backed by a municipality’s full faith and credit weren’t as ironclad as once thought, because pensioners received priority over some bondholders in the court battle over limited government funds. Gunjan Banerji, WSJ, "Detroit Sees Big Demand in Muni Market Return," 4 Dec. 2018 Of course, Star Wars has an ironclad reason for bringing back dead characters, known as Force Ghosts. Adam Schubak, Popular Mechanics, "Everything We Know So Far About Star Wars Episode IX," 17 Sep. 2018 Ice swimming requires a combination of ironclad physical and mental strength. Jenny Mccoy, SELF, "All About Ice Swimming, the Extreme Sport Where Athletes Compete in Sub-Freezing Water," 23 Aug. 2018 Although someone like Attorney General Jeff Sessions may have a credible argument that his denials of contact with Russians were the results of misunderstandings, Stone's and Caputo's denials were ironclad. Aaron Blake, Washington Post, "Roger Stone’s and Michael Caputo’s damningly false denials of contact with Russians," 18 June 2018 And the thing that came to my mind is, what would a story be like if the evidence that somebody committed a horrible crime was ironclad. CBS News, "Stephen King on "The Outsider" and where his ideas come from," 22 May 2018 While new, young designers constantly break out, the ranks of high fashion are historically ironclad. Elizabeth Raiss,, "Why Do We Treat A Fashion Designer Leaving A Brand Like Someone Dying?," 14 June 2018 This is why previous U.S. presidents have held off on recognition, pending an ironclad deal. Trudy Rubin,, "Trump-Kim summit: What to watch for when they meet in Singapore | Trudy Rubin," 6 June 2018

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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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

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marked by a state of overwhelming emotion

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