The noun θύελλα describes violent atmospheric disturbances—hurricanes, whirlwinds, or severe storms characterized by rushing, destructive wind. Homer used it for battle-storm imagery and destructive tempests at sea. The word emphasizes the violent, rushing quality of the wind rather than simply rain or thunder. Hebrews 12:18 contrasts the terrifying Sinai theophany ("darkness, gloom, and tempest") with the approachability of the new covenant. The translations uniformly render it "tempest" or "storm" (Spanish "tempestad," German "Sturm"), capturing the fearsome, violent weather phenomenon that symbolizes divine otherness and power.