warning bell
Alert before trouble
A warning bell is a bell rung to signal danger or alert people to take action—historically on ships, in churches, or at railroad crossings.
Figuratively, warning bells are feelings of unease that something is wrong: Warning bells went off in my head when he asked for my password.
The singular warning bell and plural warning bells are equally common in the figurative sense.
Urgent warning signal
- signalMessage-conveying cue
- sirenWailing alert device
- klaxonElectric warning horn
- tocsinBell rung as warning
alert · notification · caution · heads-up · red flag · wake-up call · harbinger · portent
Indicator of danger
- writing on the wallObvious omen of trouble
- tip-offAdvance secret warning
- precursorSomething that comes first
- gut feelingInstinctive sense about something
intuition · hint · signal · indication · foreshadowing
Emergency heat warning device
- evacuationRemoval from danger
- emergencySerious sudden danger
- drillHole-boring device
- schoolhouseEducation facility building
firehouse · ship · buoy · railroad crossing · level crossing · smoke detector · alert system · hazard
alarm
Urgent warning signal
tocsin · alert · notification · caution · heads-up · red flag · wake-up call · harbinger · portent · omen
toll
Fee for passage
knell · chime · ding · gong · clapper · resonance · reverberation · tone · strike · tintinnabulation
red flag
Indicator of danger
- writing on the wallObvious omen of trouble
- tip-offAdvance secret warning
- precursorSomething that comes first
gut feeling · intuition · hint · signal · indication · foreshadowing
fire alarm
Emergency heat warning device
- evacuationRemoval from danger
- emergencySerious sudden danger
- drillHole-boring device
schoolhouse · firehouse · ship · buoy · railroad crossing · level crossing · smoke detector · alert system · hazard · danger signal
- alarmsalarm, fire alarm, alert, smoke alarm, burglar alarm
- alert soundsalarm, beep, buzzer, chime, doorbell
- examsexam, test, quiz, final exam, midterm
- safety alertscaution sign, danger sign, hazard sign, fire alarm, smoke alarm
- alertsalarm, alert, notification, push notifications, email alerts
- guardsguard, point guard, guardian, shooting guard, bodyguard
warning bellall-clear
Signal danger has passed
green light · go-ahead · reassurance · safe signal · clearance
warn, warning, bell, bells, warned, warns, forewarn, belfry, forewarning