Spry girl with third cut in AE (5)

I believe the answer is:

agile

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'spry' is the definition.
(synonyms)

'girl with third cut in ae' is the wordplay.
'girl' becomes 'Ag'.
'with third cut in ae' becomes 'ile' (I can't justify this - if you can you should believe this answer much more).
'ag'+'ile'='AGILE'

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(Other definitions for agile that I've seen before include "Moving quickly/easily" , "Limber" , "Able to move quickly and easily" , "Quick in movement" , "Nimble, lively" .)

I've seen this clue in The Daily Express.

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