imperceptibility

from WordNet (r) 3.0 (2006)
imperceptibility
    n 1: the property of being imperceptible by the mind or the
         senses [ant: {perceptibility}]
from The Collaborative International Dictionary of English v.0.48
Imperceptibility \Im`per*cep`ti*bil"i*ty\, n.
   The state or quality of being imperceptible.
   [1913 Webster]
antiflux / dictionary / imperceptibility
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