ironclad
UK: ˈaɪənklaed | US: ˈaɪərnklaed
adj. 1. Covered or protected with iron; extremely sturdy or resistant.
adj. 2. (Figurative) Rigorously binding or unbreakable (e.g., a contract or argument).
n. 1. A 19th-century warship armored with iron plates.
The word "ironclad" emerged in the early 19th century, combining "iron" (from Old English īsern, referring to the metal) and "clad" (from Old English clāthod, meaning "covered or clothed"). Originally describing ships armored with iron plates to withstand cannon fire, the term later expanded metaphorically to describe anything exceptionally strong or unyielding. The logic mirrors physical durability (iron) extending to abstract resilience (e.g., agreements).
The ironclad battleship revolutionized naval warfare in the 1860s.
Their contract was ironclad, leaving no room for loopholes.
The castle’s ironclad gates resisted all attacks.
Her argument was ironclad, backed by undeniable evidence.
Modern cybersecurity systems aim to be as ironclad as possible.