undetectable

adjective

un·​de·​tect·​able ˌən-di-ˈtek-tə-bəl How to pronounce undetectable (audio)
-dē-
Synonyms of undetectablenext
: 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
ˌən-di-ˈtek-tə-blē How to pronounce undetectable (audio)
-dē-
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.
Today, Prum takes medication to keep her HIV to undetectable levels in her body, preventing health complications. — Durrie Bouscaren, NPR, 6 Aug. 2026 Aguilar said treatment had suppressed the amount of the HIV virus in her husband’s blood to undetectable levels. — Vera Lucia Pappaterra, Miami Herald, 5 Aug. 2026 The best bras for older women address sagging, loss of volume, and other changes that come with aging, while remaining stylish and undetectable under clothing. — Jenny Berg, InStyle, 29 July 2026 Dioxins have a half-life in the body of seven to 11 years, according to the World Health Organization, and lead can also be undetectable in blood but still remain in the body, bound to bones, for decades. — Angus Chen, STAT, 22 July 2026 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

Rhymes for undetectable

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Browse Nearby Words

undetd
undetectable
undetected
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Cite this Entry

“Undetectable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undetectable. Accessed 12 Aug. 2026.

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