Synset

impossible or difficult to perceive by the mind or senses
<adj.all>

sample sentences

"an imperceptible drop in temperature"
"an imperceptible nod"
"color is unperceivable to the touch"

lexical pointers

antonym

derivationally related form

imperceptibility

semantic pointers

also see

impalpable inaudible, unhearable invisible, unseeable

similar to

impalpable incognizable, incognoscible indiscernible, insensible, undetectable subliminal unobservable