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undetectable

ADJECTIVE
imperceptible
Synonyms
STRONGEST
gradual inaudible indistinguishable insignificant invisible microscopic subtle
WEAK
ephemeral evanescent fine impalpable imponderable inappreciable inconsiderable inconspicuous indiscernible indistinct infinitesimal insensible minute momentary shadowy slight small tiny trivial unnoticeable vague
Antonyms
WEAK
apparent conspicuous distinct evident noticeable obvious perceptible seeable striking unobscured
ADJECTIVE
imponderable
Synonyms
STRONG
ephemeral fine gradual infinitesimal intangible minute slight small
WEAK
evanescent impalpable inappreciable inaudible inconsiderable inconspicuous indiscernible indistinct indistinguishable insensible insignificant invisible microscopic momentary shadowy subtle tiny trivial unnoticeable unobservable vague
Antonyms
STRONG
big huge important large rough significant substantial thick
ADJECTIVE
inappreciable
Synonyms
WEAK
ephemeral evanescent fine gradual impalpable imponderable inaudible inconsiderable inconspicuous indiscernible indistinct indistinguishable infinitesimal insensible insignificant intangible invisible microscopic minute momentary shadowy slight small subtle tiny trivial unnoticeable unobservable vague
ADJECTIVE
unnoticeable
Synonyms
WEAK
ephemeral evanescent fine gradual impalpable imponderable inappreciable inaudible inconsiderable inconspicuous indiscernible indistinct indistinguishable infinitesimal insensible insignificant intangible invisible microscopic minute momentary shadowy slight small subtle tiny trivial unobservable vague
ADJECTIVE
unobservable
Synonyms
WEAK
ephemeral evanescent fine gradual impalpable imponderable inappreciable inaudible inconsiderable inconspicuous indiscernible indistinct indistinguishable infinitesimal insensible insignificant intangible invisible microscopic minute momentary shadowy slight small subtle tiny trivial unnoticeable vague

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The FDA released a major study finding most U.S. infant formula products contain low or undetectable levels of contaminants.

From The Wall Street Journal • Apr. 29, 2026

Yet while the structure is designed to be undetectable from the inside, it’s a full-blown metallic colossus on the outside — visible from the surrounding L.A. freeways.

From Los Angeles Times • Apr. 13, 2026

By the end of the study period, SIV levels were suppressed to undetectable levels in both groups.

From Science Daily • Jan. 21, 2026

But now her cancer is undetectable and she needs only annual check-ups.

From BBC • Dec. 8, 2025

The movement is so subtle that it is almost undetectable, but slowly, very, very slowly, the statue reaches to accept the rose.

From "The Night Circus" by Erin Morgenstern