English Reference
Noun

ironclad

n. countable
C2 Proficiency US /ˈaɪɝnˌkɫæd/ UK /ˈaɪəŋklæd/ iron·clad UK spelling ironclads Military

n.a large, powerful ship with a metal armor covering. These ships were used in the past to protect against enemy attacks.

n.a warship protected by a metal plating, typically iron or steel. Historically significant in the transition from wooden sailing vessels to modern naval architecture.


SIMPLE

The ironclad was the most powerful ship in the harbor.

CONTEXTUAL

During the mid-nineteenth century, the introduction of the ironclad changed the nature of naval warfare forever.

COMPLEX

The CSS Virginia, originally a steam frigate, was converted into an ironclad to challenge the Union's naval blockade of the southern ports.

As I made clear in Kyiv last week, our commitment to supporting Ukraine from Russia’s illegal invasion is ironclad.

The Guardian· 1 Sept 2026

Five years ago, a seemingly ironclad test of whether something was conscious was to see if you could have a conversation with it.

ScienceDaily· 5 Jun 2026

From iron + clad.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C2 · Proficiency
Frequency Occasional
Updated