of unknown origin
idiom
—used to say that the source or cause of something is not known
a disease of unknown origin
Examples of of unknown origin in a Sentence
Recent Examples on the Web
One morning, members of the Fort Greely missile defense base spot an ICBM of unknown origin on a suborbital trajectory heading straight for Chicago, baffling the country’s top intelligence and defense teams who only have 18 minutes to respond before impact.
—
Jake Kring-Schreifels, Time, 27 Oct. 2025
Before that, Munich Airport in Germany had to shut down for hours after drones of unknown origin were seen in the sky nearby.
—Jordan King, MSNBC Newsweek, 10 Oct. 2025
In this horror comedy, a teenage girl and her younger brother must survive a wild 24-hours during which a mass hysteria of unknown origin causes parents to turn violently on their own kids.
—Kirby Adams, The Courier-Journal, 19 Aug. 2025
However, Israel Police later confirmed that the ancient church ruins were undamaged and that the fire, of unknown origin, was confined to a nearby open area.
—Amelie Botbol, FOXNews.com, 10 Aug. 2025
Shooting down drones Americans developed a keen interest in hostile drones over the last couple of years as hundreds of pilotless aircraft of unknown origin ran forays over Air Force bases and overflew cities.
—Ray Stern, AZCentral.com, 2 July 2025
Plus, the post-credits scene of Shang-Chi and the Legend of the Ten Rings saw Shang-Chi strategizing about a threat of unknown origin with Wong (Benedict Wong), Captain Marvel (Brie Larson) and a mysteriously de-Hulked Bruce Banner (Mark Ruffalo).
—Siddhant Adlakha, Vulture, 2 May 2025
His legs were covered in puncture wounds of unknown origin.
—Rachel Raposas, People.com, 21 Feb. 2025
Fire of unknown origin destroyed the home of Mr. and Mrs. Joseph Carlson in St. Lawrence Township last Sunday.
—Contributed Content, Twin Cities, 6 Feb. 2025
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Jake Kring-Schreifels, Time, 27 Oct. 2025
Before that, Munich Airport in Germany had to shut down for hours after drones of unknown origin were seen in the sky nearby.
—Jordan King, MSNBC Newsweek, 10 Oct. 2025
In this horror comedy, a teenage girl and her younger brother must survive a wild 24-hours during which a mass hysteria of unknown origin causes parents to turn violently on their own kids.
—Kirby Adams, The Courier-Journal, 19 Aug. 2025
However, Israel Police later confirmed that the ancient church ruins were undamaged and that the fire, of unknown origin, was confined to a nearby open area.
—Amelie Botbol, FOXNews.com, 10 Aug. 2025
Shooting down drones Americans developed a keen interest in hostile drones over the last couple of years as hundreds of pilotless aircraft of unknown origin ran forays over Air Force bases and overflew cities.
—Ray Stern, AZCentral.com, 2 July 2025
Plus, the post-credits scene of Shang-Chi and the Legend of the Ten Rings saw Shang-Chi strategizing about a threat of unknown origin with Wong (Benedict Wong), Captain Marvel (Brie Larson) and a mysteriously de-Hulked Bruce Banner (Mark Ruffalo).
—Siddhant Adlakha, Vulture, 2 May 2025
His legs were covered in puncture wounds of unknown origin.
—Rachel Raposas, People.com, 21 Feb. 2025
Fire of unknown origin destroyed the home of Mr. and Mrs. Joseph Carlson in St. Lawrence Township last Sunday.
—Contributed Content, Twin Cities, 6 Feb. 2025
Cite this Entry
“Of unknown origin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/of%20unknown%20origin. Accessed 4 Nov. 2025.
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