cold case

American  

[kohld keys] / ˈkoʊld ˈkeɪs /

noun

1. a criminal investigation that has remained unsolved for an extended period of time.

   This year's award recipient is a state trooper whose work helped close a cold case from 1983.

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Etymology

Origin of cold case

First recorded in 1970–75

Example Sentences

Marx states that he reported the incident to law enforcement years later; the local sheriff’s office has denied having any cold case, missing persons case, or other report that supports Marx’s story.

From Slate • Jun. 29, 2026

Renée Ballard, who collaborates with Stilwell on that cold case, has starred or co-starred in several novels of her own.

From The Wall Street Journal • May 22, 2026

The public’s on-again, off-again interest kept Smart’s disappearance in the news sporadically, but a podcast called “Your Own Backyard,” begun in 2019 by Chris Lambert, shined a new spotlight on the cold case.

From Los Angeles Times • May 6, 2026

Last week, the Nanterre cold case unit launched a broader investigation into Pelicot's "criminal trajectories" to identify other possible crimes and victims.

From Barron's • Jan. 19, 2026

"A cold case is a case that hasn't been solved. My dad told me that while we were watching a mystery show on TV."

From "Scream for Ice Cream: Nancy Drew and the Clue Crew, #2" by Carolyn Keene