In a way that can not be seen; in an invisible manner.(adverb)
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Use "invisibly" in a sentence
"If the temperature of the air be still higher its solvent power will be still further increased, and more aqueous vapor can be taken up invisibly from a watery or humid surface."
"New research by University of Minnesota psychologists shows how social support benefits are maximized when provided "invisibly" -- that is, without the support recipient being aware that they are receiving it."
"She began hotly upbraiding him, and maintaining that the prince had only praised Natasha to deceive him by a show of kindness, all in order to destroy their attachment, with the idea of invisibly and imperceptibly turning Alyosha against her."