ironclad
n. countable C2 Proficiency US //ˈaɪɝnˌkɫæd// UK //ˈaɪəŋklæd// iron·clad
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.
The ironclad was the most powerful ship in the harbor.
During the mid-nineteenth century, the introduction of the ironclad changed the nature of naval warfare forever.
The CSS Virginia, originally a steam frigate, was converted into an ironclad to challenge the Union's naval blockade of the southern ports.
From iron + clad.