A warning of danger is a message that is sent to ALERT people of potential harm or risk. The term can be expressed in various ways, such as 'ALARM' (5 letters), 'ALERT' (5 letters), and 'sematic' (7 letters). An ALARM is a loud sound or signal that is used to warn people of danger, while an ALERT is a warning that is sent out to inform people of a potential threat. A sematic is a sign or symbol that is used to indicate a warning of danger.