imperceptibly

imperceptibly
    adv 1: in an imperceptible manner or to an imperceptible degree;
           "the power of the Secretary of State in London increased
           gradually but imperceptibly" [syn: {imperceptibly},
           {unnoticeably}] [ant: {noticeably}, {observably},
           {perceptibly}]
    

Imperceptible \Im`per*cep"ti*ble\, a. [Pref. im- not +
   perceptible: cf. F. imperceptible.]
   Not perceptible; not to be apprehended or cognized by the
   senses; not discernible by the mind; not easily apprehended.
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         Almost imperceptible to the touch.       --Dryden.
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         Its operation is slow, and in some cases almost
         imperceptible.                           --Burke.
   -- {Im`per*cep"ti*ble*ness}, n. -- {Im`per*cep"ti*bly}, adv.
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         Their . . . subtilty and imperceptibleness. --Sir M.
                                                  Hale.
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