imperceptible

adjective

im·​per·​cep·​ti·​ble ˌim-pər-ˈsep-tə-bəl 

: not perceptible by a sense or by the mind : extremely slight, gradual, or subtle

imperceptible differences

imperceptibly

ˌim-pər-ˈsep-tə-blē 

adverb

Synonyms of imperceptible

• invisible
• subtle
• indistinguishable

Examples of imperceptible in a Sentence

These changes will be imperceptible to most people.

a slight difference in hue between the two glasses that's imperceptible unless they're placed side by side

Recent Examples on the Web

The building has no ramps as the designers kept all slopes to a gentle two percent that’s virtually imperceptible. — Edward Keegan, Chicago Tribune, 19 Sep. 2026

Behaviorists emphasized observable behavior, which could be measured experimentally, and generally avoided using imperceptible internal mental states to explain behavior. — Encyclopedia Britannica, 8 Sep. 2026

That nearly imperceptible shift in the winds drifting from the nearest football stadium? — Matt Piper, New York Times, 5 Sep. 2026

Movie genres wax and wane over time in a way that can be borderline imperceptible. — Owen Gleiberman, Variety, 22 Aug. 2026

Word History

Etymology

Middle English, from Middle French, from Medieval Latin imperceptibilis, from Latin in- + Late Latin perceptibilis perceptible

First Known Use

15th century, in the meaning defined above

Rhymes for imperceptible

• acceptable
• perceptible
• susceptible
• unacceptable

Kids Definition

imperceptible

adjective

im·​per·​cep·​ti·​ble ˌim-pər-ˈsep-tə-bəl 

1

: not noticeable : not perceptible by a sense or by the mind

one whose beauty was imperceptible to others

2

: hardly noticeable : very small or gradual

an imperceptible smile

imperceptibly

-blē 

adverb