1. impossible or extremely difficult to notice or detect

Examples

• The change in temperature was almost imperceptible.
• She gave an imperceptible nod to signal her agreement.
• The crack in the wall was imperceptible to the naked eye.
• His breathing became so shallow it was nearly imperceptible.
• The shift in her mood was imperceptible to most people.
• The car moved forward at an imperceptible pace.
• There was an imperceptible tremor in his voice.