In an authentic manner; with the requisite or genuine authority.(adverb)
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Use "authentically" in a sentence
"The very act of writing authentically is one of rebellion."
"The power of using the social aspects of the web to grow your business is in authentically sharing your transparent self."
"I don't ever think or say that it's impossible for someone to write authentically from the point of view of someone on a lower rung of the power pyramid; the pyramid model itself is just a representation/theory, that's useful for discussions of why it's easier to write up the lines of power rather than the reverse."