Doctor shall host ladies of great age (2,3,2,3,5)

I believe the answer is:

as old as the hills

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'great age' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'doctor shall host ladies' is the wordplay.
'doctor' indicates anagramming the letters.
'shall'+'host'+'ladies'='shallhostladies'
'shallhostladies' anagrammed gives 'AS OLD AS THE HILLS'.

'of' acts as a link.

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I've seen this clue in The Irish Times.

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