sang-froid

noun

1. coolness of mind; calmness; composure: They committed the robbery with complete sang-froid.

noun

1. composure; self-possession; calmness

n.“presence of mind, composure,” 1712, from French sang froid, literally “cool blood,” from sang “blood” (from Latin sanguis; see sanguinary) + froid “cold” (from Latin frigidus; see frigid).