Quicken (10)

I think it could be either:

Which length description are you looking for?:

advance

'quicken' is the definition.
(thesaurus)

This is all the clue.

(Other definitions for advance that I've seen before include "necessary to be recognised?" , "borrowed money" , "Go ahead - forward - loan" , "Put forward (a theory)" , "Forward - loan - make progress" .)

I've seen this clue in The Guardian.

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