"Steel-nerved" is an adjective that refers to someone who remains calm and composed during difficult or stressful situations. Some synonyms for this term include "unflappable", "imperturbable", "unruffled", "steadfast", "resolute", "level-headed" and "unshaken". Each of these words emphasizes the individual's unwavering resolve and ability to maintain control in challenging circumstances. For example, someone who is "unflappable" is not easily upset or disturbed by any situation, while someone who is "steadfast" remains firm and unwavering in their beliefs or actions. No matter which synonym you choose, it becomes clear that being "steel-nerved" is an admirable trait that sets individuals apart in tough times.