danger signal
Sign of peril
A danger signal is any sign or warning that indicates potential harm, risk, or trouble ahead.
Originally referring to physical signals like warning lights or sirens, the phrase extends to figurative warnings: His evasiveness was a danger signal that something was wrong.
In medicine, danger signals are symptoms suggesting serious conditions requiring immediate attention.
Warning or watchfulness
- alarmUrgent warning signal
- sirenWailing alert device
- red flagIndicator of danger
- cautionCareful attention to risk
flare · beacon · indicator · symptom · omen · harbinger · portent · forewarning
Morse distress code
- maydayRadio emergency signal
- distress callUrgent plea for aid
- 911Crisis response number
- evacuationRemoval from danger
rescue · flare · siren · alarm bell · panic button · emergency broadcast · air raid siren · fire alarm
Vehicle's emergency warning blinker
- caution tapeStriped hazard boundary marker
- orange coneConical road hazard marker
- reflectorLight-redirecting surface
- buoyTethered nautical signal
lighthouse · guardrail · hazmat symbol · skull and crossbones · biohazard symbol · radiation symbol · flashing light · high-visibility
Conspicuous hues signaling unpalatability
- growlLow threatening sound
- hissSharp sibilant sound
- snarlHostile vocal threat
- hacklesErectile neck feathers
puffer fish · skunk spray · poison dart frog · coral snake · bared teeth · alarm call · pheromone
alert
Warning or watchfulness
caution · flare · beacon · indicator · symptom · omen · harbinger · portent · forewarning · premonition
SOS
Morse distress code
- maydayRadio emergency signal
- distress callUrgent plea for aid
- 911Crisis response number
evacuation · rescue · flare · siren · alarm bell · panic button · emergency broadcast · air raid siren · fire alarm · smoke detector
hazard light
Vehicle's emergency warning blinker
- caution tapeStriped hazard boundary marker
- orange coneConical road hazard marker
- reflectorLight-redirecting surface
buoy · lighthouse · guardrail · hazmat symbol · skull and crossbones · biohazard symbol · radiation symbol · flashing light · high-visibility · barrier
warning coloration
Conspicuous hues signaling unpalatability
hackles · puffer fish · skunk spray · poison dart frog · coral snake · bared teeth · alarm call · pheromone
- Spycraftspy, agent, asset, covert, handler
- alertsalarm, alert, warning, notification, push notifications
- animal callsbird call, bird calls, ribbit, frog calls, peep
- lookoutslookout, watchtower, crow's nest, observation post, guard tower
- chemical signalspheromone, pheromones, chemical signals, chemical messengers, sex pheromones
danger signalall-clear
Signal danger has passed
all clear signal · green light · coast is clear · reassurance · clearance
sign, danger, signal, dangerous, signature, endanger, endangered, signify, signaling