Crossword Genius

An actor's "aside"? (5)

Ross

I believe the answer is:

apart

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Here is my best explanation:

'aside?' is the definition.
('apart' can be a synonym of 'aside')

'an actor's' is the wordplay.
'an' becomes 'a'.
'actor' becomes 'part' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a'+'part'='APART'

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