imperceptibility

Definition of Imperceptibility in English :

1. imperceptibility

the property of being imperceptible by the mind or the senses

WordNet Lexical Database for English. Princeton University. 2010.

Imperceptibility

adjective

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

adjective

not plain or distinct to the senses or the mind; esp., so slight, gradual, subtle, etc. as not to be easily perceived

adj.

1. Impossible or difficult to perceive by the mind or senses: an imperceptible drop in temperature.

2. So subtle, slight, or gradual as to be barely perceptible: an imperceptible nod.