imperceptible
adjective
1. impossible or difficult to perceive by the mind or senses
- an imperceptible drop in temperature
- an imperceptible nod
Similar word(s): inaudible, unhearable, impalpable, impalpable, incognizable, incognoscible, indiscernible, insensible, undetectable, subliminal, unobservable, invisible, unseeable, unperceivable
Sentences with imperceptible as an adjective:
- We all missed the imperceptible shake of his head as he tried to warn us without being seen.