cast-iron
🇺🇸
/ˌkæst ˈaɪərn/
🇬🇧
/ˌkɑːst ˈaɪən/
made from a strong metal called cast iron
The cast-iron skillet was perfect for frying eggs.
very strong, certain, or reliable
He gave his cast-iron assurance that the job would be done on time.