undetectable

adjective

un·​de·​tect·​able ˌən-di-ˈtek-tə-bəl How to pronounce undetectable (audio)
-dē-
: unable to be detected : impossible to discover or notice : not detectable
an almost undetectable change
undetectable traces of poison
Signs of life may be so minimal as to be undetectable by modern instruments …Lauren J. Livo
undetectably adverb
an undetectably small change

Examples of undetectable 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.
More than half didn’t know that HIV-positive people can reach undetectable status and not transmit the virus to others. Scott Malia, The Conversation, 10 Sep. 2025 Since you are no longer supposed to have any prostate tissue in your body, these levels should be undetectable. Bruce Y. Lee, Forbes.com, 6 Sep. 2025 When the right treatment is available, people can live a normal life with HIV and have an undetectable viral load. Hannah Millington, MSNBC Newsweek, 26 Aug. 2025 Within a year, 16 participants saw their virus rebound and resumed treatment — but four remained in remission, with undetectable viral loads. David Cox, NPR, 25 Aug. 2025 See All Example Sentences for undetectable

Word History

First Known Use

1863, in the meaning defined above

Time Traveler
The first known use of undetectable was in 1863

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Cite this Entry

“Undetectable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undetectable. Accessed 16 Sep. 2025.

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