Starting price fairly active (9)

I believe the answer is:

sprightly

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'active' is the definition.
(I've seen this before)

'starting price fairly' is the wordplay.
'starting price' becomes 'sp' (abbreviation in betting).
'fairly' becomes 'rightly' (I can't explain this - if you can you should believe this answer much more).
'sp'+'rightly'='SPRIGHTLY'

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(Other definitions for sprightly that I've seen before include "Active" , "Moving nimbly" , "Vivacious" , "Agile" , "Lively" .)

I've seen this clue in The Telegraph.

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