canary in the coal mine
Early danger indicator
A canary in the coal mine is an early warning sign of danger or trouble.
The phrase comes from the mining practice of bringing canaries underground because the birds would die from toxic gases before levels became fatal to humans, giving miners time to escape.
Today it describes any indicator that signals a larger problem: The failing local businesses were a canary in the coal mine for the region's economic collapse.
One who foreshadows
- omenProphetic indicator
- precursorSomething that comes first
- signalMessage-conveying cue
- indicatorSign revealing status
forewarning · herald · bellwether · portent · foreshadowing · red flag · early warning · alarm
Insider who reports misconduct
- test caseLawsuit establishing legal precedent
- early adopterFirst purchaser of innovations
- bellwetherTrend-setting leader
- leading indicatorMetric forecasting future conditions
proxy · litmus test · barometer · weathervane · touchstone · benchmark · guinea pig · frontline
Ease of breaking
- exposureState of being unprotected
- susceptibilityLiability to influence
- defenselessnessState of being unprotected
- sensitivityResponsiveness to stimuli
delicacy · expendability · sacrifice · victim · scapegoat · martyrdom · helplessness · weakness
Simplest alkane fuel
- ventilationCirculation of fresh air
- shaftNarrow vertical passage
- tunnelEnclosed underground route
- undergroundBelow ground or countercultural
explosion · toxic fumes · carbon monoxide · mineshaft · pit · excavation · lamp · safety
harbinger
One who foreshadows
indicator · forewarning · herald · bellwether · portent · foreshadowing · red flag · early warning · alarm · alert
whistleblower
Insider who reports misconduct
- test caseLawsuit establishing legal precedent
- early adopterFirst purchaser of innovations
- bellwetherTrend-setting leader
leading indicator · proxy · litmus test · barometer · weathervane · touchstone · benchmark · guinea pig · frontline
fragility
Ease of breaking
- exposureState of being unprotected
- susceptibilityLiability to influence
- defenselessnessState of being unprotected
sensitivity · delicacy · expendability · sacrifice · victim · scapegoat · martyrdom · helplessness · weakness · peril
methane
Simplest alkane fuel
- ventilationCirculation of fresh air
- shaftNarrow vertical passage
- tunnelEnclosed underground route
underground · explosion · toxic fumes · carbon monoxide · mineshaft · pit · excavation · lamp · safety · colliery
canary in the coal minehindsight
Recognition after the fact
red herring · postmortem · wolf in sheep's clothing · autopsy · smoke and mirrors
canary in the coal minecockroach
Flattened scavenging household insect
survivor · last man standing · ironclad · bulletproof · invulnerable