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

With a milky texture, the sunscreen blends into the skin with an undetectable finish, and the product is fragrance-free. —Jenny Berg, Vogue, 1 May 2025

Before the creation of this new test, the new variant was undetectable by other mpox PCR tests. —Stephanie Edwards, Discover Magazine, 20 Feb. 2025

The drug first underwent human trials in 2023, where it was found to be safe and tolerable among patients, and reduced Lp(a) to undetectable levels for nearly one year. —Jamie Ducharme, Health, 14 Apr. 2025

By doing so, the virus will drop to undetectable levels, restoring the CD4 count to where the body is better able to fight infection.6 There are currently over 25 antiretroviral agents used to control HIV. —Anju Goel, Verywell Health, 22 Mar. 2025

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