Crossword Genius

Derision shown by audience rapping three old actors (8)

Ross

I believe the answer is:

histrios

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'derision shown by audience rapping' is the definition.
I know nothing about this answer so I can't judge whether this works.

'three old actors' is the wordplay.
I cannot quite see how this works, but
'three' could be 'trio' (synonyms) and 'trio' is found within the answer.
The remaining letters 'hiss' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...

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I've seen this clue in The Times.
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