have nerves of steel
To have the ability to stay calm at all times, even during pressure-filled situations. If you're going to be a neurosurgeon, you need to have nerves of steel—there's no time to panic when you're operating on someone's brain. My mother had nerves of steel, and she never backed down from danger.
have nerves of steel
not be easily upset or frightened.have nerves of ˈsteel
not be easily frightened in a difficult or dangerous situation: She won’t be nervous about doing it. She’s got nerves of steel.