1. false alarm - Noun
2. false alarm - Phrase
a warning that is given about something that fails to occur
Source: WordNetAs Brzezinski prepared to phone President Jimmy Carter to plan a full-scale response, he received a third call: It was a false alarm. Source: Internet
Constant false alarm rate and digital terrain model processing are also used in clutter environments. Source: Internet
Petrov correctly assessed the situation as a false alarm, and hence did not report his finding to his superiors. Source: Internet
But the siren turned out to be a false alarm. Source: Internet
A spokesman for SFRS said: “The call out to Ipswich Hospital was a false alarm. Source: Internet
Firefighters responded to a general fire alarm at 2:35 p.m. in the 2000 block of Weld County Road 23. It was a false alarm. Source: Internet