panic: [17] Panic is etymologically ‘terror caused by the god Pan’. The ancient Greeks believed that he lurked in lonely spots, and would frighten people by suddenly appearing, or making noises. He was evidently invoked to account for alarming but harmless natural phenomena, and so the element of ‘irrationality’ in the English word was present from the beginning. English acquired it (originally as an adjective) via French panique and modern Latin pānicus from Greek pānikós ‘of Pan’. => pan[panic etymology, panic origin, 英语词源]