ironclad

1 of 2

adjective

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

ironclad

2 of 2

noun

iron·​clad ˈī(-ə)rn-ˌklad How to pronounce ironclad (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
Why introduce that friction to a friendship that is so ironclad? — Kennedy French, Variety, 13 May 2026 This is an ironclad obligation, as firefighters put their lives on the line every day to protect Chicagoans. — Chicago Tribune, 26 Apr. 2026
Noun
The ironclad’s tenure at sea was short-lived, however. — Andrew Paul, Popular Science, 11 Mar. 2026 Likewise, there is no ironclad guarantee that a short-form conversation will always get a suitable detection and be flagged. — Lance Eliot, Forbes.com, 29 Aug. 2025 See All Example Sentences for ironclad

Word History

First Known Use

Adjective

circa 1847, in the meaning defined at sense 1

Noun

1862, in the meaning defined above

Time Traveler
The first known use of ironclad was circa 1847

Rhymes for ironclad

See All Rhymes for ironclad

Browse Nearby Words

iron chloride
ironclad
iron curtain
See all Nearby Words

Cite this Entry

“Ironclad.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ironclad. Accessed 7 Jul. 2026.

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Kids Definition

ironclad

1 of 2 adjective
iron·​clad -ˈklad How to pronounce ironclad (audio)
1
: covered by iron armor
2
: rigorous sense 1, exacting
ironclad laws

ironclad

2 of 2 noun
iron·​clad -ˌklad How to pronounce ironclad (audio)
: an armored naval vessel
Last Updated: - Updated example sentences
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