undetected
adjective
un·de·tect·ed
ˌən-di-ˈtek-təd 
-dē-
: not observed, noticed, or detected
an undetected flaw/error
an undetected illness
These rare mistakes are subtle and may go undetected for months and even years.—
Mario Salvadori
Mario SalvadoriExamples of undetected in a Sentence
Recent Examples on the Web
If there are regions where public health officials never report illnesses with rashes and fevers, for example, that’s a red flag that measles could be spreading undetected.
—Stephanie Pappas, Scientific American, 3 Nov. 2025
Strong infection-control policies at that time also helped reduce the potential for unreported or undetected Covid-19 cases, the researchers said.
—Deidre McPhillips, CNN Money, 31 Oct. 2025
As per the research team, neutrinos are crucial to understanding the universe due to their ability to pass through matter almost undetected.
—Georgina Jedikovska, Interesting Engineering, 23 Oct. 2025
Coiba's isolated nature has allowed for narco activity to occur undetected along the island’s shores, according to authorities.
—Maya Duclay, ABC News, 23 Oct. 2025
See All Example Sentences for undetected
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Stephanie Pappas, Scientific American, 3 Nov. 2025
Strong infection-control policies at that time also helped reduce the potential for unreported or undetected Covid-19 cases, the researchers said.
—Deidre McPhillips, CNN Money, 31 Oct. 2025
As per the research team, neutrinos are crucial to understanding the universe due to their ability to pass through matter almost undetected.
—Georgina Jedikovska, Interesting Engineering, 23 Oct. 2025
Coiba's isolated nature has allowed for narco activity to occur undetected along the island’s shores, according to authorities.
—Maya Duclay, ABC News, 23 Oct. 2025
See All Example Sentences for undetected
Cite this Entry
“Undetected.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undetected. Accessed 13 Nov. 2025.
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