blue canary
n.— «As miners once used caged canaries to warn them of poisonous gas underground, the greatest fear of these two streetwise veterans is a “blue canary,” a police officer or emergency worker who unknowingly walks into his or her demise.» —“Homeland Security In St. Louis” by Phillip O’Connor St. Louis Post-Dispatch (Missouri) Mar. 23, 2003. (source: Double-Tongued Dictionary)
Further reading
Karina from Maryville, Missouri, disagrees with her mom about whether bowl and bull sound the same. Karina hears them as the same sound, while her mom hears a clear difference. It’s an example of a vowel merger, or sound shift, that occurs in...
When a teenager went a week without talking as part of a school project, he noticed a surprising side effect: Instead of rehearsing a response to what other people were saying to him, he was focused on listening — and feeling smarter as a result...