A one-way girl (4)

I believe the answer is:

anne

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

'a one-way' is the wordplay.
'one' becomes 'nn' (I can't justify this - if you can you should believe this answer much more).
'way' becomes 'e' (Compass direction - East).
'a'+'nn'+'e'='ANNE'

Can you help me to learn more?

(Other definitions for anne that I've seen before include "First queen of Great Britain and Ireland" , "Female name" , "Boleyn or Hathaway, say" , "Second or fourth wife of Henry VIII" , "One of the Bronte' tens" .)

I've seen this clue in the Evening Standard.

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