undetected

adjective

un·​de·​tect·​ed ˌən-di-ˈtek-təd How to pronounce undetected (audio)
-dē-
Synonyms of undetectednext
: 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

Examples of undetected in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
During the Hugging Face breach, OpenAI agents autonomously plotted a digital heist that went undetected for more than a week, intensifying concerns OpenAI is sacrificing safety to push the AI frontier. — Reuters, NBC news, 4 Sep. 2026 Many affected health zones are in areas where cases go undetected or unreported for several reasons, including distrust in health authorities. — ABC News, 3 Sep. 2026 So far, these measures include nationwide HIV screenings before surgeries to flag undetected infections, and a complete ban on certain types of syringes from January, a move that first started after the Larkana outbreak 7 years ago. — Betsy Joles, NPR, 2 Sep. 2026 This may have led to delays in correctly identifying clusters of illness as Ebola, as AP reports that experts believe the virus may have been spreading undetected as early as February. — Cara Lynn Shultz, PEOPLE, 2 Sep. 2026 See All Example Sentences for undetected

Word History

First Known Use

circa 1602, in the meaning defined above

Time Traveler
The first known use of undetected was circa 1602

Rhymes for undetected

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Browse Nearby Words

undetectable
undetected
undeterminable
See all Nearby Words

Cite this Entry

“Undetected.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undetected. Accessed 7 Sep. 2026.

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