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.
These illustrative figures exclude initial implementation and later consequences of undetected errors. — Swapnil Upganlawar, Forbes.com, 26 Oct. 2026 The Bundibugyo strain of the virus spread undetected for months before the ​outbreak was declared in May. — Reuters, NBC news, 23 Oct. 2026 But the exploit, which took advantage of a weakness that had gone undetected for more than a decade, worked. — Harry Booth, Time, 23 Oct. 2026 It's not considered to be a complete cure, instead settling for HBV's DNA and viral protein – HBsAg – remaining undetected for 24 weeks once all other treatment has been stopped. — New Atlas, 22 Oct. 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 1 Nov. 2026.

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