imperceptible

American  

[im-per-sep-tuh-buhl] / ˌɪm pərˈsɛp tə bəl /

adjective

1. very slight, gradual, or subtle.

   the imperceptible slope of the road.

2. not perceptible; not perceived by or affecting the senses.

   Synonyms:

   undetectable, unperceivable, hidden

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noun

1. something not capable of being perceived by the senses.

   metaphysical speculation about imperceptibles.

imperceptible British  

/ ˌɪmpəˈsɛptɪbəl /

adjective

1. too slight, subtle, gradual, etc, to be perceived

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Other Word Forms

• imperceptibility noun
• imperceptibleness noun
• imperceptibly adverb

Etymology

Origin of imperceptible

From the Medieval Latin word imperceptibilis, dating back to 1520–30. See im- ², perceptible

Explanation

If it's imperceptible, it's impossible to perceive with any of the senses. The world might be spinning, but it's imperceptible from your couch. Within the word imperceptible you see the word percept, which means "the object of your perception." Like impossible, the im in imperceptible means it cannot be perceived. Imperceptible is rarely used in the absolute sense of the word — it is usually paired with almost. Horton hears the Who but the tiny sounds of the Whos were almost imperceptible to everyone else.

Example Sentences

But the opposite, reflective face bears an image incised in finely engraved lines that under normal conditions is virtually imperceptible to the naked eye.

From The Wall Street Journal • Nov. 12, 2025

"Traditionally, the intense heat of firing destroys any biological residue. However, our technique has been able to reveal fingerprint ridges that would otherwise remain imperceptible."

From Science Daily • Nov. 2, 2025

The weirdly urgent task lies in asking ourselves whether we have become unwitting accomplices in the imperceptible attempts to make some people unseeable, and why we might be willing to accept that.

From Slate • May 21, 2025

Richards, also known as Mister Fantastic, has the ability to stretch his body to the extreme, while his partner, Sue — a.k.a. the Invisible Woman — is imperceptible and can manipulate force fields.

From Los Angeles Times • Feb. 4, 2025

Step by step it evolved, so slowly as to be nearly imperceptible.

From "Do Androids Dream of Electric Sheep?" by Philip K. Dick

Related Words

• gradual
• inaudible
• indistinguishable
• insignificant
• invisible
• microscopic
• subtle
• undetectable