A metaphor for the constant and impending threat of danger or harm that hangs over someone, often used to describe the conditions of both power and vulnerability. It is an allusion to the ancient Greek legend of Damocles, who during a dinner with King Dionysius II had a sword hanging over his head, suspended by a horsehair thread. The sword was placed there by the king himself, who wished to illustrate the constant threat of danger that came with being in a position of power.