ironclad

Từ điển WordNet v3.1 - WordNet Dictionary

I - noun

a wooden warship of the 19th century that is plated with iron or steel armor
• Hypernyms:
warship, war vessel, combat ship

II - adjective

1. sheathed in iron plates for protection
• Similar to:
sheathed
2. inflexibly entrenched and unchangeable
- brassbound traditions
- brassbound party loyalists
- an ironclad rule
• Syn:
brassbound
• Similar to:
inflexible