undetectable

adjective

un·​de·​tect·​able ˌən-di-ˈtek-tə-bəl 

-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

ˌən-di-ˈtek-tə-blē 

-dē-

adverb

an undetectably small change

Examples of undetectable in a Sentence

Recent Examples on the Web

Its oil-free formula relies on chemical UV filters to deliver sun protection that feels virtually undetectable. — Madison San Miguel, Allure, 10 Nov. 2026

Your provider will discuss antiretroviral therapy (ART), which can reduce the virus to undetectable levels. — Md Published, Verywell Health, 23 Oct. 2026

However, iVerify did not establish that the malware is completely undetectable. — Kurt Knutsson, FOXNews.com, 19 Oct. 2026

After 72 hours of recovery, researchers found that cortisol was undetectable in all but one dogfish. — Maria Mocerino, Interesting Engineering, 17 Oct. 2026

Word History

First Known Use

1863, in the meaning defined above

Rhymes for undetectable

• collectable
• collectible
• correctable
• delectable
• detectable
• expectable
• injectable
• protectable
• resectable
• respectable
• selectable
• uncollectible