ENGLISH
REFERENCE

canary in a coal mine

idiom
Meaning

Something whose sensitivity to adverse conditions makes it a useful early indicator of such conditions; something which warns of the coming of a greater danger or trouble by a deterioration in its health or welfare.


Origin

disputed origin

An allusion to caged canaries that miners would carry down into the mine tunnels with them. If dangerous gases, such as carbon monoxide collected in the mine, the gases would kill the canary before killing the miners, thus providing a warning to exit the tunnels immediately.

Examples
SIMPLE

Rising prices are the canary in a coal mine for the economy.

CONTEXTUAL

The sudden drop in local sales acted as a canary in a coal mine, warning the company of a larger financial crisis.

COMPLEX

The rapid decline of the local bee population served as a grim canary in a coal mine, signaling that the entire ecosystem was facing an irreversible collapse.

Anchors to
Related idioms3entries
  1. 01

    canary fit

    A highly emotional state of distress, anger, etc.

  2. 02

    cat that ate the canary

    A person who appears self-satisfied or smug, especially while concealing something mischievous, prohibited, or private.

  3. 03

    miners' canary

    Any thing, especially an organism, whose demise or distress provides an early warning of danger.

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