a legendary courtier who extravagantly praised the happiness of Dionysius I, ruler of Syracuse. To show him how precarious this happiness was, Dionysius seated him at a banquet with a sword hung by a single hair over his head.
Phrases
sword of Damocles
used to refer to an extremely precarious situation.
Derivatives
Damoclean
adjective
Damocles in other Oxford dictionaries
Definition of Damocles in the US English dictionary