invisibly

from WordNet (r) 3.0 (2006)
invisibly
    adv 1: without being seen; "these organisms enter the body
           invisibly" [ant: {visibly}]
from The Collaborative International Dictionary of English v.0.48
Invisibly \In*vis"i*bly\, adv.
   In an invisible manner. --Denham.
   [1913 Webster]
antiflux / dictionary / invisibly
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