adj

ironclad

Ironclad (adj) means So solid or certain that it cannot reasonably be disputed or broken. Example: “The contract came with an ironclad guarantee.”

adj

So solid or certain that it cannot reasonably be disputed or broken.

"The contract came with an ironclad guarantee."

"She had an ironclad alibi for the night of the robbery."

noun

Historically, a warship protected by iron or steel armor plating.

"The battle between two ironclads changed naval warfare forever."

How to use ironclad

Learner’s notes

In plain EnglishExtremely solid and dependable — used mostly for agreements, alibis, or guarantees today.

Common pairings

ironclad contract ironclad alibi ironclad guarantee

Word forms

more ironclad comparative, ironclads plural, most ironclad superlative

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The contract came with an _____ guarantee.

Etymology

From iron plus clad ("clothed, covered") — literally "covered in iron," originally describing armored warships.

Frequently asked questions

What does “ironclad” mean?

The word “ironclad” means so solid or certain that it cannot reasonably be disputed or broken. In plain terms, extremely solid and dependable — used mostly for agreements, alibis, or guarantees today.

How do you use “ironclad” in a sentence?

Here is “ironclad” used in a sentence: “The contract came with an ironclad guarantee.”

What part of speech is “ironclad”?

Depending on how it is used, “ironclad” can be an adjective and a noun.

How many meanings does “ironclad” have?

“Ironclad” has 2 distinct senses listed in this dictionary. The most common is: so solid or certain that it cannot reasonably be disputed or broken.