In actuality (6)

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2,5

really

factis

'in actuality' is the definition.
(thesaurus)

This is all the clue.

(Other definitions for really that I've seen before include "are you sure?" , "Actually, in fact" , "Go on" , "without a doubt" , "In truth - one may be surprised to say it" .)

I've seen this clue in The Independent, The Wall Street Journal and The New York Times.

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