Warning signs are symbols or indicators that alert people to potential danger or risk. They can come in the form of PORTENTS (8 letters), alerts (6 letters), and OMENS (5 letters). PORTENTS are signs that something is about to happen, usually of a negative nature. Alerts are urgent warnings that something is happening or about to happen. OMENS are signs that are interpreted as having a supernatural origin, often predicting misfortune. All three terms can be used to refer to warning signs.