blue canary n. an emergency worker (especially a police officer or first responder) whose death alerts other personnel to a hazardous situation. Etymological Note: From the use of canaries in coal mines, whose death would alert miners to the presence of dangerous gases. (source: Double-Tongued Dictionary)
Further reading
Asthenosphere, a geologist’s term for the molten layer beneath the earth’s crust, sparks a journey that stretches all the way from ancient Greece to the author of Uncle Tom’s Cabin. Plus: What the heck is a dogberg? It’s when...
The adjectives canine and feline refer to dogs and cats. But how does English address other groups of animals? Plus, cabin fever has been around much longer than the current pandemic. That restless, antsy, stir-crazy feeling goes back to the days...
While the word “respondent” does in fact, according to merriam-webster.com mean “one who responds,” I believe it is more common among those in the heroic professions to refer to themselvese as first responders as opposed to first respondents. Though I’m certainly no authority on the subject, I most often hear the word “respondent” in connection with civil proceedings at law or surveys.
I think you’re right. I’ll change the definition accordingly.