Meaning of “cast-iron” - Learner’s Dictionary


adjective us uk /ˈkɑːstˌaɪən/
NO DOUBT [ always before noun ]

able to be trusted completely, or impossible to doubt:

I need a cast-iron guarantee that the work will be finished on time.

made of cast iron

(Definition of “cast-iron adjective” from the Cambridge Learner’s Dictionary © Cambridge University Press)