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

• 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

Deepfakes can be detected by analyzing pixel-level abnormalities that are imperceptible to humans. —Rohan Pinto, Forbes.com, 17 June 2025

Among adults and adolescents, there was no difference at all between the two groups; among children, the differences were so minor as to be almost imperceptible. —Paul Tough Eric Jason Martin Krish Seenivasan Brian St. Pierre, New York Times, 13 Apr. 2025

The notes are basically imperceptible, and the one note the speakers can hit seems to leap out of nowhere in the mix. —PC Magazine, 4 June 2025

Five years later, the outlines of these words are almost imperceptible. —Alfredo Sosa, Christian Science Monitor, 18 May 2025

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