1
Undetectable change
Too small from one moment or measurement to the next to be noticed without comparison or instruments.
Example
The glacier's daily movement is nearly imperceptible.
imperceptible
/ˌɪmpərˈsɛptəbəl/ · im-per-SEP-tuh-buhladjective
Impossible or extremely difficult to perceive.
Use imperceptible for a change, movement, sound, or difference too slight for ordinary observation to detect.
What imperceptible Really Means
The word becomes easier to use when its closely related senses are separated and compared.
2
Extremely faint sensation
Too slight for ordinary sight, hearing, touch, or another sense to register clearly.
Example
The device emitted an almost imperceptible hum.
3
Subtle difference
So fine that its effect may be recognised only through careful analysis.
Example
A nearly imperceptible shift in tone changed the sentence's meaning.
Use imperceptible Naturally
Notice how the surrounding noun or clause reveals the exact shade of meaning.
A nearly imperceptible shift in tone changed the sentence's meaning.
The glacier moves each day, but the displacement is imperceptible without precise instruments.
An imperceptible delay between sound and image made the recording feel slightly unnatural.
Precision Matters
Imperceptible overlaps with several common words, but each carries a different emphasis.
imperceptible
vs.May be too slight to notice at all.
subtle
Is delicate or not obvious but can still be perceived.
imperceptible
vs.Can concern any sense or form of perception.
invisible
Specifically cannot be seen.
imperceptible
vs.Describes detectability rather than importance or practical effect.
negligible
Means too small or unimportant to matter.
imperceptible
vs.May describe a change that is too slight to notice at a particular moment.
gradual
Describes slow progression but may remain clearly observable.
Test imperceptible in Context
The change occurs, but its daily scale is too small for ordinary observation.
1
The glacier advances several metres each year, yet its movement from one day to the next is nearly ___ without specialised measuring equipment.